Archive of Our Own ^beta

Chapter Text

Donnie knew he shouldn’t exactly have taken them. Knew there was no way this was normal brother behavior. Sure, he didn’t actually have much knowledge on what normal brother behavior looked like, but he was sure it wasn’t this.

He loved machines, had since he was young. Easily able to take something apart and put it back together easily. And it had come naturally to him.

This naturally meant that when something broke, it was his job to fix it.

Meaning half of the things he was working on at any time were for one of his brothers or Splinter. Occasionally April. 

That day it just happened to be Leo’s tv. Most of them had been gotten out of the trash so it wasn’t unusual for any of them to break down. And he would have just taken it down to his lab to work on, but with a little look at it, it was going to take him half an hour max. Not at all worth the amount of effort it would take to carry it back to his lab. Or to get laughed at by Raph as he asked for his help carrying it.

Halfway through Leo had said, “I’m just going to go check on the others,” before stepping out for a few minutes. Donnie had only really responded with a grunt, focused on the tv. Only realizing once Leo had gone that he had left.

Eyes wandering around the room with the rare chance to do so. Along with looking for his brother of course.

He had trailed over them at first, not being super obvious. Under a few other things. A small amount of mess, out of place for the normally clean freak Leo. It was always the easiest to fix something in Leo’s room with it being so clean.

Then he had realized what he had just seen. Eyes going wide as he looked back at them. Staring at the pair of light purple panties. Just lying there. Almost calling out to Donnie in a way he didn’t really like.

He could hear his brother’s foot steps coming back, still staring at the panties. Plain cotton and not at all anything special. They didn’t actually need clothes, didn’t wear them more often than not. But that didn’t mean they never wore anything, obvious by the fabric sitting in front of him. 

He had barely thought about it as he shoved them in one of his tool boxes, not his main one where he was going to be getting things from often. Leo wouldn’t even notice they were in there.

He felt like Leo could tell. Eyes boring into the back of Donnie’s head as he finished up, trying to go as fast as he could. Just hoping that the space in his mind filled by the panties wasn’t too much to mess with how well he was fixing the tv. That way he didn’t have to come back too quickly.

Running away as soon as he could, as soon as the tv was fixed. Walking fast to his lab, head turned down. Looking at the floor as he went. Sure Leo was confused in his room. 

Once he had gotten back into the lab, he slammed the door closed. Collapsing against it, panting more than he should for the fact that he hadn’t actually been running away. Just walking rather fast but not fast enough that if any of his brothers had seen him they would have thought anything was wrong.

With the reminder of his brothers, it just dug in the panties now stuck in his tool box belonged to his brother. His brother who he had to see every day.

He thought about just throwing them back into the laundry. They would then get sorted out into Leo’s pile, who normally did the laundry anyways. And no one would suspect anything.

With a sigh, Donnie pushed himself off of the door, finally setting his things down. Hesitating with a hand above the opening of his tool box. Convincing himself that he was just going to put the panties back into the laundry. Better yet throw them away. Knowing that Leo would never get the nerves up to ask anyone where they went, assuming they had been lost somewhere. Then he wouldn’t have to deal with any of this. 

But opening up his tool box and seeing the purple cotton he knew there was no way in hell he was giving this up. Instead sighing again as he just stared down at them, wondering what the hell he should do with them now.

Not having much time to think however before the lab door was attempted open before loud knocking followed making Donnie jump. Mikey’s voice following. Probably another thing he needed fixed. Donnie sighed before throwing the panties towards some of the clothes he’d been meaning to take to his room, taking only a minute to bury them, yelling that he was coming.

They had stayed there for a day or so, Donnie almost forgetting about them after taking his clothes back to his room. Not until he finally got around to putting them away that he had run into the panties once again. Face growing hot as he looked down at them. Having only realized they were there once they were already in his hands.

Standing frozen still. Not moving an inch. Just staring down at the fabric in his hands. 

Of course he knew he was alone in his room but he couldn’t help himself but look around himself, just to make sure of it. Biting down on the inside of his cheek, tearing slightly at the soft flesh there. Most of the doors didn’t have locks on them, so he couldn’t make sure that no one would come inside. But he was glad that he at least had decent enough hearing as he finally decided what he was going to do with them. Wishing not for the first time in his puberty ridden teenage years that he had an actual lock on his door. One day he was going to fix that as well but it was very low on the ever growing list of things he needed to fix.

His attention was brought back to the panties in his hand as they unconsciously flexed around the purple fabric. Face flushing hot. Embarrassing himself with his behavior.

But that didn’t stop him from slowly, hesitatingly, bringing the panties up to his face. Once again hesitating for only a moment before shoving his face in them. Breathing in the scent of Leo like never before. Even however days old the scent that was so clearly Leo stuck to the fabric. Donnie not able to hold back a loud groan, dick dropping into the cold air of the sewers. 

He was quick to wrap a hand around it, squeezing tightly around the base with a moan. Taking another deep breath in as he dragged his hand up slowly, not wanting to blow too soon. Gripping the panties even harder against his face.

It was such a wonderful scent and all Donnie could think about was getting more of it. Wanting to bury his face in the source. Drink up the beautiful scent for hours at a time.

God he was a pervert.

The worse kind of pervert, the kind who was currently thinking about eating out his brother.

But even with all the guilt, he couldn’t get himself to stop. Couldn’t pull the panties away from his face or stop his hand around his cock. His mind continuing to supply him beautiful pictures of Leo succumbing to pleasure, all of it given to him by Donnie.

Picturing Leo beneath him as he ate him out, holding on tight to the sheets or to the ends of Donnie’s mask. Trying to pull Donnie’s face in closer. Or even trying to pull his head away, so sensitive and overstimulated that all he could do was whine and beg for Donnie to stop. Not that Donnie would, trying to get more of the taste and scent all at once.

He finally collapsed onto his bed, hand moving even faster over his cock. Thinking about seeing Leo wearing these very panties. Normally Donnie didn’t pay attention to that area of his brothers, hadn’t exactly thought about Leo like this before.

Sure he’d known he had an incest kink, watching maybe a little too much step sibling porn, but he hadn’t thought anything of it. That was normal, knew it wasn’t something that would indicate that he wanted to actually fuck any of his brothers.

Clearly he had been wrong. 

Staring down at his cock in his hand while thinking about fucking Leo hard and fast while sniffing his panties. But he was too far gone for much guilt to really perpetrate his mind. Any thought like that quickly being thrown out of his head when the Leo in his head placed a hand on the side of his head. Turning his face towards him, locking eyes with him.

Giving him that soft smile that made his whole face soften up, the one that always made Donnie feel safe and a warm feeling spread through his lower stomach— oh fuck. This was not something new.

That information made him groan but he pushed it to the side. He could think about that later. About his true feelings for his brother when his hand wasn’t wrapped around his cock and he wasn’t trying to cum.

So instead he continued with the thoughts of Leo. Leo turning Donnie to face him, moaning so softly and whining for more, “Please Don,” fantasy Leo said softly, legs wrapping loosely around Donnie’s shell, “hurry.” Voice a whine and just forcing another groan out of Donnie, making his hand speed up. He knew Leo would never actually say anything like that, for multiple reasons, but god was the thought hot as fuck.

His mouth had fallen open with all of his pants and moans, tongue coming out to lick at his lips. Forgetting about the panties near his mouth. Eyes rolling back into his head at the slight taste. Even days old he swore he could taste Leo on the fabric. Far enough gone that he didn’t even think as he brought the panties down, licking at the fabric. 

Fantasies going back to eating Leo out. Even if the taste wasn’t clear, it was good enough. Enough that he could put together what Leo’s pussy would actually taste like. Thinking about Leo’s thighs wrapping around his head, his own thrown back against Donnie’s pillows. Whining and begging for more. For Donnie to finally fuck him. 

In the real world, Donnie could feel himself getting closer. Hand speeding up and getting more sporadic. No longer the even pace he liked to keep. His lust filled brain came up with a wild and insane idea. A small part of him knowing it was a crazy idea but ultimately being ruled out by the horny side of his brain. 

Readjusting himself to be sitting on his knees still on his bed, one hand pressing the panties against the bed and the other still on his cock. Bringing himself closer and closer. Imagining that it was Leo below him instead of just his panties. Leo’s face pulled together in pleasure and looking up at Donnie with half lidded eyes, moaning loudly and not caring about who around them heard.

“Please Donnie,” Fantasy Leo moaned out, heels digging into the back of Donnie’s thighs, “I need you to cum inside me so badly.”

That did it. 

Donnie groaning as he came across the panties. A bigger load than normal. It hadn’t even been that long since he’d last jerked off, the only thing he could think of being that he had actually thought about Leo to get off this time. 

As he finally came down from his orgasm, it fully hit him just what he’d done. The panties in front of him covered in his cum. Eyes falling shut and falling down on the bed. Figuring he’d just deal with all of this in the morning. He really wished he could just pass out even after doing something like that. It would give him no time to wallow in his guilt.

But his mind continued to whir, thinking about what he was going to do with the panties. Knowing what he should do with them now. But having another idea of what he could do with them. 

Chapter Text

“They were left in with my stuff,” Donnie said, shoving a piece of fabric in his hands before saying a quick, “Bye I’ve got stuff to do,” words practically running into each other as Donnie ran away.

Leo watched the back of his head with confusion. Only looking down at the fabric that had been shoved into his hands after Donnie had left. Face flushing at the panties in his hands. Walking back to his room. He’d thought he’d lost this pair, last he’d seen them they’d been on his floor. And it was odd for any of his clothes to be sorted wrong as he was the one who did the laundry. Including sorting everything.

And looking at them as he pushed open the door to his room, they looked more stained than last he’d seen them. All of this along with Donnie’s weird behavior just made him think that something was definitely up. But he didn’t have long to think before Raph texted saying there were some gang members out for them to beat up. So he shrugged. 

While technically he didn’t need underwear, he didn’t usually wear them around the house, it was just better to wear a pair and a small pair of short while out. Just to protect himself from anything. So he quickly pulled the panties in his hand up, grimacing slightly at the cold feeling, before pulling up a pair of plain black shorts. Heading out to find Mikey and Donnie already waiting for him.

Donnie seemed to be back to normal, staring at his own phone and rattling off Raph's location. Leo would have to scold Raph later for going out on patrol by himself. Again. The third time this week.

Unfortunately things were worse than he thought from Raph’s texts so he didn’t have time to think too hard about anything let alone tell his brother off for going out on his own. Instead throwing himself into fighting. 

As the fight dragged on, Leo was getting more and more uncomfortable. It was easy to kind of brush off the whole thing with the fact that he was fighting, sword dragging through the air loudly next to his head. But it got harder and harder to ignore. Readjusting himself every few minutes, only having a few moments to do so every time.

Along with that, as the fight was going, he couldn’t help but feel eyes on the back of his neck. Normally he might have just brushed it off as some gang member staring at him, about to attack. But every time he turned around it was the same person every time.

Donnie was looking at the back of his head. Staring with wide almost unblinking eyes. Staring for a few seconds longer before realizing he’d been caught. Turning back around to actually watch what he was doing. Which only made Leo wonder what was happening even more.

Finally every last person who needed to, had gotten their ass kicked. And they could finally go home, Leo lecturing Raph all the way back. Ignoring the weird feeling he had in his lower areas and the eyes still on the back of his head.

Letting Raph off the hook a little earlier than he would have on any other day and heading to his room once they got back to the lair. Giving the excuse of wanting to go read and parting ways with the rest of the group. Catching Donnie’s eyes who still was staring with that wide unblinking look. Head tilted just slightly before he was pulled off by Mikey to go do something or another. Leo was already out of hearing range when they started speaking. 

Instantly pulling the panties off looking down at the mess between his thighs with confusion. Nothing should have made him more wet than normal or anything. He wasn’t someone who got — aroused during fights or anything so there should be no reason why his panties were more wet than before.

Because they had definitely been dry when he’d put them on earlier. And Donnie had said they had gotten mixed with his clothes. So they should be clean. It’s not like he’d just picked up a pair off the floor or anything.

He thought for a moment, trying to think of what it could be. Mind coming up with various ideas. Before something seemed to click. Face warming as he stared down at where the panties were still wrapped around his thighs, yet to be moved since he’d discovered the problem.

Suddenly remembering when Donnie had come to fix his tv. He’d had to leave the room for fear of his brother figuring out that watching Donnie work was causing him to have feelings a brother shouldn’t feel for another brother. It hadn’t been long after he’d come back into his room that Donnie had finished, practically running out of the room and leaving Leo confused in his wake.

But he hadn’t thought about it for too long, his walk having not done much for how turned on he’d become. Glad he hadn’t had to wait for long to get himself off.

Thinking back on it now however, the panties had gone missing around that time, or at least he had noticed them missing soon after. And the last place he remembered them being having been on the floor next to where Donnie would have been working.

The thought just made Leo bring his hands up to cover up his face as it continued to grow more and more red. As if hiding his embarrassment from someone even if he knew that only he was in the room. The only one who might see him would be if Donnie actually had a camera in his room, a fantasy Leo had admittedly gotten off to more times than he would like to admit.

He slowly pulled them away from his eyes, looking down to the panties he now suspected were covered in his brother’s cum. Which he had rewetted just by wearing them. It just made his face somehow more hot, sure he looked more like a tomato than a turtle at the moment.

At the same time he couldn’t help the way he throbbed at the idea. He didn’t have anything else to do today. Normally he would wait until almost everyone was asleep, although he was sure Donnie was still up with his atrocious sleep schedule, before he would do anything like this. But he couldn’t help it, too aroused to do anything and it being too early for a cold shower to not be noticeable. Even with their mission, too much time had passed. 

Someone would mention it. As such there was no other choice.

He pulled the panties back up, almost forgetting they had been around his thighs still, biting down on his lip at the feeling. Walking over to his bed, reaching under for the small box which held the few toys he’d gotten his hands on. Going instantly for his favorite.

It was made of a purple silicone, a similar color to the panties he was wearing. Not the biggest dildo he’d ever seen, he’d thought some of the sizes on the website he’d looked at had been horrendous and was sure none of them would ever fit inside of him, but it was rather thick. About the same thickness as the thickest part of his forearm. The website had said it was around 6 inches but he’d never actually checked it but looking at it he was sure that from the base of the fake balls to the tip was at least half an inch off.

But he didn’t really care about any of that, for now putting it to the side. Just wanting to get it out for when he was ready for it. Bringing over his favorite pillow for just this scenario, placing it between his thighs. Hesitating for just a moment before dragging his hips down gasping at the pleasure exploding through him at the action.

No longer hesitant, gripping the edge of the pillow as he rutted against it. Pressing himself down more, a small whine escaping from his mouth. Eyes shut tight.

He could feel what he now knew was cum against him, sure it was just being rubbed further into his skin, wondering if any of it would end up inside himself. Wondering what Donnie had thought about when he’d jerked off using the panties.

Presumably it had been about him, but Leo wished he could ask. Wondering just what Donnie wanted to do to him, just how long he’d been thinking about Leo.

Digging his hips in further to the pillow as he thought about Donnie. Of him watching Leo with those same eyes he’d given him earlier. Now sure that Donnie had been thinking about the panties. Wondering if Leo had them on, maybe had even known that was why Leo had been readjusting himself all afternoon.

A moan left him again, fists tight around the pillow, trying to press it harder against himself, as his thoughts continued. The panties in his hands, gripped tight as he jerked himself off, thinking about Leo below him. Maybe wrapping the fabric around his cock as well, saturating the whole of the fabric in his cock. He was always so quiet and Leo wondered if that transferred to the bedroom. Silently panting as he fucked his fist, thinking about fucking into Leo instead of his hand. Softly moaning Leo’s name as he came into the panties.

But what got Leo even more was that he not only gave them back to Leo covered in his release, but that he had hand delivered them. Could have just set them on Leo’s bed at some point and Leo never would have figured out what happened. Might have thought it was weird but wouldn’t have thought too much of it.

Instead he had made sure Leo had known the panties had landed in Donnie’s room somehow. A flimsy lie Leo didn’t know if it came from his brother coming up with the idea too close after his orgasm or if it had been a conscious choice. Wanting Leo to know who it was that had came on his panties, whose cum it was close to his most personal area.

That idea made Leo finally sit up straight, hands still gripping the pillow beneath him as he came with a small stutter of his hips. Biting down on his lip for fear that he would moan out too loudly and his brothers who were still very much awake would come in wondering what had happened.

Leo sat still for a minute, panting before he pushed the panties off, grabbing his dildo. Staring at the seat of the panties, his brother’s cum now mixing with Leo’s own slick, only kind of visible now. But he was sure it was still there. Placing the head of the dildo at his hole, biting down on his lip again as he debated this very weird idea.

Pressing down with a soft moan and taking another glance at the panties, saying a small, “fuck it,” and pressing the seat of the panties, where he knew the cum had been, to his mouth. Knowing he was smelling the combination of his brother’s cock and his own pussy. Tentatively pressing his tongue to it, eyes rolling into the back of his head as he unintentionally pushed more of the dildo inside of himself than he meant to. Moan muffed by the panties he was currently licking cum off of. Possibly days old or even just a day old. But he knew it had been Donnie’s.

Not able to stop himself as he continued to press himself down and licking the panties. Trying to get as much of his brother as he could. Wanting so badly for Donnie to be here where he could get it straight from the source. 

Mind drifting to what Donnie would say if he saw this. He’d thought that Donnie would reject any advances he could have made, but this gave him some kind of evidence that his brother might feel even slightly the same way as him. Would at least want to fuck Leo even if that was all he could ever have, it would be fine with him. Thinking of Donnie above him, head thrown back and moaning as he shoved his cock into Leo’s mouth, hand pressing on the back of his head.

Leo had heard something about the quiet ones being freaks, clear by the cum in his panties he was currently licking up. Hand delivered to him. Leo moaned at the idea of Donnie fucking his mouth hard and rough, wishing he had more hands to simulate the feeling any more than he could. Instead he looked up, imagining Donnie above him, saying, “Good boy taking all of my cock.” Another loud moan forced out of him as he got down to the wide base of the dildo.

Sitting still, panting into the panties, trying to let himself get used to the feeling again. He always had to just to make sure. Not wanting to be too hurt or even just limping around, both would get him too many questions. Questions he wouldn’t want to answer to his brothers.

Eventually, shorter than he probably should have, he picked himself back up. Pausing with just the head inside him before dropping back down much faster than he had before. Moaning into the panties he was sure he’d cleaned of cum by now but he couldn't bring them away from his face. Not yet.

Instead setting a nice even pace, bouncing up and down on the fake cock. Fantasies changing up. Thinking instead that it was Donnie’s cock he was riding. His nerdy brother’s hands on his thighs, a small reminder he was there but he didn’t move. Words soft and encouraging. Praising him for doing so well.

The fake words just made Leo speed up, biting down on his lip to suppress his moans. Wanting so badly to moan out, scream out, his brother’s name. But that would bring way too much attention to him. Couldn’t even do that late at night. And it was so rare for him to be alone in the sewers being the leader he was normally one of the ones on missions. So if only one person was staying behind it wasn't him.

Leo’s hips speed up, thinking about Donnie earlier that week, before any of this bullshit. They'd run into some bomb, Donnie instantly diving into disarming it. He’d been so quick about it and Leo’d had to fight to continue paying attention to the enemies in front of him. Always loving to watch Donnie work.

The way his arms would bulge just a little, showing off the small amount of muscle he had. Most of his strength not something you could see in the same way you could see it on Raph. It was one of his favorite things about watching Donnie work in his lab, watching him pick up things that looked so heavy and like he would have to call in Raph to pick up and yet he carried them so easily. 

Then he was so intensely focused on whatever he was fixing. Only getting a little annoyed when they all asked him multiple times when he was going to be done disarming the bomb. Putting all of his attention on the bomb, the mission at hand. The exact same expression he’d had when staring at Leo earlier that day.

And then after the mission, once everything was fine again, on their way back to the sewers, Donnie had gone on a nice monologue about the type of bomb it was and how impressive it was. Either ignoring or just not noticing how Mikey and Raph continued to complain about his nerd shit. Leo on the other hand had thought it was so hot. Loving how passionate Donnie was about his work.

He was sure that the way Donnie fucked was probably a good in-between of them. Passionate about pleasing Leo but also able to throw him around. And of course Leo could easily fight back if he wanted to but he wouldn’t. Instead would submit easily.

He was starting to slow down. Even with all of his training, his thighs were starting to burn from the angle. Instead flipping himself onto his back, holding the base of the dildo as he moved. Easily bringing his thighs up before resuming his motions, able to get back to the same fast pace he’d gotten before but with a little less pain now. Position exposing everything to the door if anyone walked in.

Along with it the position made his mind wander to another point he’d made earlier. The idea that Donnie was watching him right now.

Of course Leo knew his brother had cameras around the lair and probably didn’t have ones in their rooms. But he couldn’t help but moan out at the idea of Donnie in his lab. Watching his computer with Leo’s room pulled up, maybe just watching as Leo fucked himself, maybe jerking himself off.

But now he would be able to see everything. Equipment probably easily able to zoom in right on where the fake cock was fucking into Leo’s hole, maybe imagining it was his cock that was fucking Leo. Just the same way that Leo was imagining right now.

Leo could feel himself getting closer, head falling back as he tried to keep his thrusts even but failed miserably. Having to try even harder to keep himself quiet, feeling moans and other noises of pleasure bubbling up his throat and threatening to come out. Bringing his other hand down, rubbing quick and fast at his clit. Finally feeling himself fall over that edge, mouth falling open in a silent scream. Only thing going through his mind being Donnie’s name.

Thrusts all but stopping as he came around the fake cock, imagining that Donnie had cum inside of him. But made sure to thrust all the way inside, moaning out right next to Leo’s ear, “Gonna fill you with my kids.” The idea making a whimper escape his silence and a small whine of his brother’s name. Finally collapsing back against the pillow.

Laying there silently, staring up at the ceiling for a moment. Thinking over what he’d just done. Throwing the panties into be washed, glad he was the one who did laundry so he didn’t have to explain to one of his brothers why his panties were soaked. Mind once again wandering to the idea that Donnie was watching him right now, a small dreamy smile coming over his face. Not able to hold back a laugh.

Yeah right.

Chapter Text

Donnie was still staring at the screen in shock and awe. Having just come down from his own orgasm, panting as he did so. 

He’d hung out with Mikey for only a few minutes after getting back from their mission. Mind already off the idea that Leo had been wearing the panties Donnie had cum in when he had walked into his lab. Washing his hands as he always did before sitting down at his computer to start his work.

The cameras were already up as before he’d gotten the text from Raph, he’d been a little worried about where his brother had gone off to. He knew he should just get on with his work as there wasn’t going to be anything exciting happening right then. But with a small shrug he’d flipped through the cameras.

Most of the rooms had been empty just as Donnie had known they would be as there would have been an alert if someone had come in who hadn’t been approved. Mikey and Raph had been in the living room arguing over something or another but it didn’t seem to be anything too serious. Master Splinter had been in the Dojo meditating. And Leo had been in his room. Back facing the camera.

And then Donnie had watched his brother rutting against his pillow to fucking himself on a dildo while licking at the panties Donnie had cum onto. Maybe he should have flipped away but he couldn’t help watching as he jerked off. Swearing softly when his brother had whined his name, looking directly at the camera, stunning Donnie and forcing his own orgasm out of him. 

Now he had to clean himself up and figure out how he was going to look his brother in the eyes later.

Instead he threw himself into his work, going back to what he was originally here for. After cleaning himself up of course. Going back to the blood samples he’d gotten from his brothers. Making sure everything was going as healthy as could be. Something he did every month, making sure they were healthy.

As often happened, he missed breakfast the next morning, not having even realized he’d been going all night. But he still needed to eat before he probably took a quick nap instead of fully sleeping as he should. He’d figured since he had missed breakfast, he would have the kitchen all to himself, either grabbing a small amount of whatever had been made that morning or something quick. Anything he could take into the lab to continue the work he should have been working on last night before he collapsed into bed.

“Hey Donnie,” Leo said with a wide smile on his face, plate full of food in his hands. Donnie’s eyes widened but he was quick to try and keep his face neutral, although it wasn’t too hard for him thankfully. 

“Hey Leo,” He said still frozen in the entrance.

Leo tried to hold back a laugh, holding the plate out to him, “I was just about to bring this to you.” Leo said taking a few steps forward. Donnie had to fight the urge to walk further back, “I guess you had some good timing.”

“I guess.” Donnie said with a nervous laugh, taking the plate from his brother. Forcing himself to keep looking at Leo, “Well I was just going to grab some food and head back up to my lab so I’ll see you later.” Donnie’s words were fast as he turned on his heel to hurry back to the lab.

“I’ll follow you,” Leo said causing Donnie to turn around suddenly.

“What?” He asked trying not to seem too suspicious.

“There was something I want to,” Leo paused, biting his bottom lip, “discuss with you.”

Instantly Donnie’s mind whirled with all of the things that Leo could have possibly wanted to talk to him about, none of them good for Donnie. Maybe he somehow knew about the cameras in the rooms, knew that Donnie had watched him jerk off last night. Maybe he knew that this wasn’t the first time Donnie had watched his brother jerk off, although he normally clicked off a lot sooner than he had last night. 

But he tried not to let any of these thoughts come through in his movements. Nodding stiffly at Leo with an equally tense smile before heading back to the lab. Feeling his brother’s eyes on his back, so intense. 

He went right over to his desk, setting the plate down and hearing the door close behind Leo. Stiffening for a moment as he heard Leo lock the door, the only door in the lair that had a lock on it. Usually just to keep out Mikey. 

This time it felt like a death sentence.

Donnie instantly stuffed his mouth with eggs, trying to think of any guesses at what Leo wanted to talk about. As far as he knew his brother just wanted to discuss one of the many upgrades Donnie was working on at the moment. Or any of the things that he was fixing up around the house.

Once again he had to try not to flinch at Leo sitting down on the seat next to him, leaning on the table slightly. He didn’t speak, probably waiting for Donnie to at least finish what was in his mouth now. Donnie didn’t bother sticking more in his mouth, figuring it was probably better to just get it over with now.

“I kind of lied,” Leo said, “I have a few things I wanted to talk to you about,” before launching into question Donnie about his touch ups on the comms. Donnie let out a sigh of relief, talking as he ate. Doing his best to talk while eating.

“I’m getting so close,” Donnie said, setting his fork down against his plate, “hopefully once I’m done we should be able to hear each other much easier.”

“That’s great Don,” Leo said, Donnie sitting up a little straighter at the praise, “there was one other thing I wanted to discuss though.”

“Go for it,” Donnie said, pushing his plate away from him.

“Did you think it would be a fun way to tell me how you feel?” Leo asked, face set carefully on his hands. It took Donnie a moment to fully understand what he meant, still on the various projects he was working on. Face flushing the moment he realized what Leo was talking about.

“W—what?” Donnie asked, voice more high pitched than he would have liked. Leo’s face looked rather innocent, more innocent than expected with the subject they were talking abut.

“Returning my panties to me,” Leo said, rolling the stool closer to Donnie, “covered with your cum. Or did you just think I wouldn’t notice?”

Donnie couldn’t make himself look Leo in the face, turning around with a nervous laugh, “I don’t know what you’re talking about.”

“Sure Don,” Donnie hadn’t noticed how close his brother had gotten, feeling his breath on his shoulder, “come on. There’s no need to lie to me. I’m not mad about it.”

Donnie had known that but he sure as hell couldn’t tell Leo that. Instead Donnie kept quiet, not sure what the hell he was supposed to say. Sure his face was still bright red.

“It’s kind of hot,” Leo said, voice dropped now to barely a whisper, “and very flattering.”

There was only so much that Donnie could reasonably take, slowly turning his head. And once he actually looked at Leo, he couldn’t hold himself back. Their faces so close to each other, Donnie quickly closing the distance. Pressing their mouths together. Leo moaned into the kiss, quickly getting up and pushing away the stool and sitting on Donnie’s lap.

It was hard for the two of them to fit together, Donnie’s hands quickly coming up to hold his brother still. Not caring that his hands were right under his shell, on his ass. Especially at the moan Leo let out, pressing them closer together. Arms wrapping around Donnie’s neck, one hand pressing down Donnie’s shell while the other came up to the back of his head, playing with the tails of his mask.

As the kiss became more intense, it got harder and harder to keep holding Leo up. He made the decision quick, making sure his grip on Leo was good, he stood up, Leo letting out a soft gasp against his mouth. Donnie didn’t have to walk far to set his brother on the table, standing between his legs. 

The kiss quickly was brought back up to speed, Donnie feeling himself throbbing and knowing he would drop any second now. But he also didn’t know how far Leo actually wanted to go. Pulling away briefly, intending on having an actual conversation but his words were caught in his throat.

Leo’s face was flushed, mouth plump and red from where they had been kissing. His chest was heaving as he tried to get his breath back. The flush didn’t happen to be just on his face, going all the way down his body, leading Donnie to between his brother’s thighs. Eyes going wide at the sight of his brother’s pussy on fully display, plush thighs pulled apart.

All ideas of trying to talk going out the window. Instead only able to drop down to his knees. Hearing vaguely as Leo tried to say something but he was cut off by Donnie pressing his mouth to Leo’s pussy. Only able to moan out at the feeling. Hands coming instantly to press against the back of Donnie’s head. Pushing him further into heaven. Donnie didn’t hesitate, licking his way up, collecting as much of his brother’s taste onto his tongue. 

Just as he had thought, Leo tasted divine. But this was so much different than licking at Leo’s panties. Straight from the source was different, better. A whole lot better.

He brought his hands up, gripping tight at Leo’s thighs, moaning against his brother’s pussy. The vibrations making Leo leak more onto his tongue. Donnie feeling Leo’s thighs clench around his head, heels right against his shoulder, trying to push him in further. Which Donnie gladly did, pressing his tongue inside Leo’s hole, trying to get more of the delicious nectar.

Pulling another loud moan from his brother, throwing his head back. Thighs only tightening around Donnie’s head more. Making Donnie feel like he had died and truly gone to heaven. Although he assumed this would instantly damn him to hell. But if it felt this damn good, he would willing walk into hell. Probably right after Leo and his delectable pussy.

Hearing yet another moan, he couldn’t help but glance up at Leo who had looked down at Donnie. Face flushed and one hand brought up from pushing at Donnies head to cover his mouth. Although it seemed to do nothing to cover up his noises. Not that Donnie wanted him to cover them up. His mouth was parted, red and puffy still from their making out.

“You taste so good,” Donnie panted, pulling away for just a second before diving back in. Leo didn’t respond to the compliment, not seemingly able to string words together. Donnie’s mind on the other hand felt like it was going a mile a minute, would have been talking his brother’s ear off if his mouth wasn’t otherwise occupied.

Bringing his mouth up, trying to put in some of the very little research he had done into practice. Actual research, not just porn. Although he had watched plenty of that too.

He knew the general area he was looking for but it was hard to find when he couldn’t exactly look. But he knew the moment he found Leo’s clit as Leo once again threw his head back, practically screaming. Heels pressing into Donnie’s shell to pull him in closer. Donnie going all too willingly. Focusing all of his attention on that spot. Feeling the slick travel down his chin, sure he would look like a total mess when he came back up. But it was all worth it to him for just a taste of Leo, loving the taste. 

“Wait, Don—” Leo said, Donnie about to pull back before his brother continued, “I I’m gonna—” fully understanding now what Leo was saying. And instead of pulling away he only got closer, bringing a hand up to thrust a finger into Leo. Crocking it upwards, looking for the spot that would throw his brother over the edge.

Forcing his brother to throw his head back again once he found it not long after, hands clutching the edge of the table as he came against Donnie’s face. Donnie gladly helping his brother through it. Only a little surprised he had managed to get his brother to squirt the first time they did this. Now the only thing going through his mind being if this was the first time Leo did squirt or if he did all the time. Then wondering if his brother was a virgin.

Coming back up after Leo had finally collapsed onto the table, chest heaving and staring up at Donnie with lidded eyes. He brought a hand up to wipe at his chin, only succeeding in spreading the slick onto his cheek. But he didn’t care, pressing his mouth to Leo’s. Leo giving a small weak moan, pushing lightly at Donnie’s chest, “You have to give me a moment,” he panted out with a small tired laugh. Donnie instantly pulled away with a quick nod.

“Right of course.” Donnie said with a nervous laugh of his own, “You don’t have to reciprocate or anything if you're too tired honestly I’m just glad that I got to do anything with you at all and if you don’t want to continue then I don't really m—”

“Donnie,” Leo eventually interrupted him, bringing a hand up to press against Donnie’s lower arm, not able to reach more then that, “I’m not saying I don’t want more, but I just came. You have to give me a moment and then I’ll help with that.”

With his brother’s words and glance down, Donnie looked where he was, flushing instantly. He hadn’t even realized he had dropped down, currently very hard. 

“Its—”

“I don’t feel obligated or something,” Leo said with a huff and a roll of his eyes, “You’re not the only one with feelings here Donnie.”

“Right,” Donnie said with another nervous laugh.

After a few moments, Leo sat up fully, Donnie instantly perking up, not able to help himself. Instead of saying anything, Leo just wrapped his arms around Donnie’s neck, bringing him in close. Pressing their lips together. Although not for long, quickly parting and saying, “Now I’m ready.”

Before Donnie could ask what that entailed, Leo got off the table, now much shorter than Donnie. Pushing on Donnie’s chest lightly and making him fall into his chair. Quickly climbing into his lap, grinding his still wet pussy down against Donnie’s cock. Making them both moan loudly. Donnie’s hands coming up to press against his brother’s hips, trying not to grip him too hard.

“I still can’t believe you would do that,” Leo groaned, grinding down once more on Donnie’s cock, head catching on his dripping hole, “rather risky to hand deliver my panties back to me covered in your cum.”

“Wasn’t really thinking,” Donnie said, face flushed and turned away, not able to look his brother in the eyes. Leo didn’t seem to like that. Hands coming up to softly grip at Donnie’s face and turning him slightly.

“I jerked off to them,” Leo said with a moan, dick dragging along his clit, “after I fully realized what you had done.”

Before Donnie really thought about it, all of the blood in his brain clearly going straight down, saying, “I know.”

At first Donnie was stared, Leo pausing his movements, about to pull back and apologies, maybe try to say it was a joke. Before Leo continued back up, grinding down harder and faster now, “God, that is so creepy Donnie,” He moaned out, “you actually have cameras in our rooms?”

There was no use lying now, Donnie nodded. Eyes now locked onto where Leo’s pussy was dragging against his cock, spreading slick all down it. 

Instead of the logical reaction, pushing Donnie off and running away, Leo moaned out, “I wished you had.” Donnie’s eyes snapped up to stare at Leo’s face. His own flush with a nervous almost manic smile on his face, “imagined you watching me fuck myself onto my dildo while I did it. Imagined that so many times.”

That revelation made Donnie’s eyes widen, “Really?”

Leo nodded violently, “Yeah, it’s so creepy.” He moaned out, “You’re such a pervert Donnie,” He paused again, slowing his hips down as he leaned in closer, “it’s a real good thing I like that,” before connecting their lips again, hands coming to the back of Donnie’s neck. Pushing their mouths closer together.

But the kiss was short, Leo quickly pulling away to look down at where they were connected. Lifting his hips to let Donnie’s cock spring up. Eyes widening at the sight.

“God I hadn’t realized you were so big.” Leo said, voice low in an almost wonderment, “There is no way that is going to fit in me.”

“You don’t have to, like I said I honestly wasn't expecting things to get this far so if you don't wan—”

“I never said I don't want to,” Leo said with a short laugh, “maybe I more of should have said it’s not going to fit without me trying real hard.”

Before Donnie could try and intervene, Leo was already lining the tip up with his hole, pressing himself down. Both of them moaning out at the feeling. Leo was so tight around his cock. Maybe a little too tight. Donnie gripping tightly at the arms of his chair as Leo sunk down slowly.

Not going all the way down before he was coming back, keeping his movements slow and taking more on every decline. Donnie just hoping that he didn’t cum before he even got all the way inside. 

Above all though he tried to keep his eyes open, watching Leo’s face. Leo, whose own eyes were closed, chin down and mouth open just slightly. Panting softly and occasionally flinching. Face still flush as he moved. Sweat starting to role down his forehead.

Donnie couldn’t bring himself to look away, cursing the fact that he even had to blink. Sure that this would be the only time he would be allowed to see this. Wanting to take in every last second, sear it into his mind so he could play it over and over again.

He had gotten so caught up in his own thoughts that he hadn’t even realized just how much Leo had taken. Only realizing when Leo gasped, eyes fluttering open as he finally fully sat in Donnie’s lap. Their eyes meeting, surprising Donnie with the intensity in his brother’s eyes. Sure that if it was possible, there would have been hearts in his eyes.

It felt like time stopped as Leo sat still for a moment, panting with a hand on Donnie’s shoulder. Gripping tight to keep himself stable. Waiting only a moment before moving his hips in small circles. Forcing a moan out of Donnie, eyes finally falling shut for a moment, forehead falling to his brother’s shoulder. Slowly creeping up to his neck. Panting into the skin there.

Leo took that as a signal. Hips coming up just a small amount before quickly, much quicker then before, falling once again. Donnie not able to hold back a small keen, biting hard into Leo’s neck. Surely making a mark there. That just made Leo moan, coming up higher with every move of his hips. Speeding up at every one.

“If you don’t slow down,” Donnie panted, voice almost a whine, “I’m going to cum way too quickly.”

That just made Leo moan, bouncing up and down faster. Donnie’s hands coming up to grip at his brother’s thighs, not truly wanting Leo to stop or even slow down. But knowing if he didn't, Donnie would embarrass himself. Trying to say it once again but Leo stopped him, pressing their lips together again. And all words escaped Donnie’s mind at that moment, not able to think about anything else but his brother. 

Hands squeezing even tighter as Leo sped up, bouncing faster and faster. Donnie feeling Leo reach in between them to rub at his clit. Donnie quickly understanding, brushing his hand aside to press his thumb against Leo’s clit. Leo moaning loudly against Donnie’s lips, not fully pulling away to speak, “Ke—eep doing that,” he moaned out. 

Donnie fully pulling away to press his forehead back to Leo’s shoulder, groaning out, “I—I’m gonna—”

Leo nodded frantically, his own hands coming to press against Donnie’s shoulders, digging in tightly. Steadying himself as he sped up, “Me too.” Donnie didn’t let his hand stop for a moment, trying to match Leo’s speed but it was getting harder and harder. Feeling himself getting closer and closer to the edge. Feeling the familiar tightness as he got so close.

“You gotta—”

Raising his head he could see Leo shaking his head, biting down a large smile, “Please,” he said, “Do it, cum inside me Donnie.”

Donnie’s eyes widened, going to shake his head but Leo stopped him, hands dragging along Donnie’s shoulders, his neck to grip at his face, “I know you want to. Bet you wished you were cumming inside me when you came in my panties.” Donnie’s eyes were stuck on Leo’s lips, watching as his brother released his lip from his teeth, “And I want you to. God I want you to so badly Donnie.” 

He came closer, voice dropping low, “I need it so badly Donnie, need your cum in me so badly,” once again taking his bottom lip between his teeth, “I need you to cum inside me so badly.”

That did it. 

Donnie feeling his vision going white as he finally came, only vaguely able to hear Leo as he came only a few seconds later. Feeling the wet slick spilling over where they were connected.

Both of them sitting there panting for a moment, each coming down from their own orgasms. Leo’s second and Donnie’s first.

Eventually Leo got up, cum spilling down his thighs. Donnie’s eyes were drawn to it, wanting to drag it back up. Push it back up inside Leo. Back where it belonged.

Instead Donnie looked away with a bright blush on his face. Watching out of the corner of his eyes as Leo cleaned himself off, having no idea where he’d gotten the cloth. Looking away again as Leo turned back to him, sitting back down in the chair he’d been in before he’d climbed into Donnie’s lap.

They were both quiet, neither saying a word. Donnie much too embarrassed now and mind going so fast it was hard for his mouth to catch up even if he wanted to actually say anything at all.

“I hope this isn’t the last time.” Leo said, forcing Donnie’s eyes over to him. Leo looked down at the table, a much small blush on his face, “I didn’t say a lie. I really have been thinking about you like that.” It was surprising to Donnie how much his brother seemed to be avoiding the words around what they did, just as nervous it seemed as him, “But also I want more than that as well.”

“I wouldn’t mind it,” Donnie said, voice quiet, hands in his lap. Not able to keep still for a moment. Leo looked over at him with a soft smile.

“Good,” he got up, pressing a kiss to Donnie’s cheek, “Don’t miss practice today.”

Before Donnie could respond he was already walking towards the door, hips swishing slightly as he did so. Donnie didn’t know if it was intentional, if that was just how his brother always walked. But he couldn't help but watch him go. Putting his head in his hands on the table the moment Leo was out the door, closing it behind him.

Wondering how the hell he had gotten here. But with a smile he was glad. Happy he had stolen those panties.