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Shouta just wanted to introduce his class to a child who needed their protection. He noticed that Bakugo had been off all week, ever since they took Eri out of Chisaki's care. Maybe it was a coincidence or maybe it was that Kirishima was hurt. He didn't know, he knew that the class had noticed as well. They all assumed that since Kirishima was back he’d be better. And he was...slightly. It seemed like there was more to the issue but of course he wouldn’t tell anyone.
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"Today i will be introducing you to someone." Aizawa starts. Katsuki was so worried, he just wanted classes to be over. He'd heard from Dabi that Eri was missing and Chisaki had been arrested. So what the fuck happened to Eri?! He needed to find out, but he couldn't because of these fucking lessons.
As much as he hated going ‘home’ he was planning to go and get as much information as he could. But he couldn’t be out late because of the fucking curfew and he can’t miss the fucking lessons and-
He took a deep breath, it's probably better to listen to Aizawa for now. He said it was important or some shit.
"You all Know some of your classmates were involved in a investigation, they managed to save a young girl." Katsuki's eyes widen, no way- "She's here so all of the teachers and you guys can protect her. Everyone on the investigation, Midoriya especially, is closer to her so done be surprised if she's scared or runs to one of them. She hasn't spoken much about herself or what happened to her, so don't make her feel strange about it."
So it's not Eri. Shit. Katsuki remembers so many time she wouldn't stop talking, they'd had so many conversations and he loves how interested she gets in small things. They're both too grown up for their age and he hates how mature she has to be.
But he loves their conversations so much. She’s so bright, like the fucking sun. Somehow she turned out so good whilst being taught so wrong. Whilst as much as Katsuki tried, he’d always be defensive, rude and brash because that’s how he’d survived.
Aizawa walks outside and the door closes, everyone asking Midoriya about the girl. When the door opens the room is silent. A girl with long white hair and red eyes walks in, holding Aizawa's hand. Katsuki's eyes widen and he jumps up, his chair falling as he does.
"Bakugo!" Aizawa glares.
"Katsu-nii?" The Girl looks at him with wide eyes and Katsuki runs over to her.
"Oh thank god." He hugs her before anyone can stop him. Aizawa wants to warn him against touch but Eri hugs back. "I didn't know what to think when they said you were missing." The class watch, amazed as he speaks to the girl like they’d known each other for years.
"I'm okay! Deku saved me!" She speaks up, loudly and smiling wide. It's a different girl then Midoriya and Aizawa had been looking after for a week.
"He did, did he?" He pulls away and kneels before her. "Well I'm glad. Do you mind telling me what happened princess?"
"I don't know all of it. Sorry." She looks down.
"Hey, hey. I'm not him remember, I'm not going to be angry at you."
"Sorry-"
"Don't apologise." He ruffles her hair. "Look at me, remember you can tell me anything."
"Right." She nods determined. "Chisaki-"
"Oh so it's dick face's fault again."
"It's always his fault!" Eri stomps her foot.
"I know princess, continue." Unfortunately being around Katsuki means that she picked up his anger.
"He was still doing the experiments and he let me rest for a minute and I managed to run outside! I found Deku and Lemillion! Deku promised he'd help me but I had to go back."
"He sent you back to him?!" Katsuki hisses and immediately turns around and glares at him, angry like none of them had seen before. "He's supposed to be a fucking hero and he sends you back to where you were being-"
"No it's okay! Katsu-nii! He helped!"
"Did he?" Katsuki raises one eyebrow, sceptical.
"They did a whole mission and Deku carried me out!"
"Huh." He looks back at the green haired boy who looks very nervous. "Guess he's off the hook." The boy in question sighs in relief.
"See!" She smiles. "And! I'm out now! Like you promised I would be! Which means it's your turn-"
"Princess that's a secret." He says quickly.
"No! I was being hurt and you promised I'd get out! I promised you! I promised you that you'd get out too! You promised you'd try-"
"Hey, angel deep breaths. Remember?" She nods and closes her eyes. "There we go, good girl. Okay so I know I promised, but remember how you didn't want anyone to know what was going on?" She nods. "I haven't told anyone either."
"But...but you can now! You're surrounded by heroes."
"That's part of the problem honey." He rubs his temples.
"Anyway." He takes a strand of her hair in his hands. "I was going to come over this week and cut your hair remember."
"Yea! I wanted it short!"
"I can't remember how short you said. Was it....here?" He taps her ear.
"Katsu-nii! Noooooo!"
"Orrrrr, here?" He points to just above where her hair ends now, just above her hip.
"Nooooo!" She pouts. He just laughs and tickles her.
"Are you sure?"
"Katsu-nii!"
"So What did you want then princess?"
"Just below my shoulders! I told you this!" She whines.
"Oh! Now I remember." She huffs and crosses her arms. "Why don't I do it later angel? Did you manage to finish reading the book I gave you? If you left it behind that's okay though, I can get you a new one." He says with a soft smile.
"I brought a bag!" She smiles widely, "I kept all the things you gave me!"
"That's good to hear. And now you're out I can finally get you some pretty dresses like you always wanted."
"Mhm!" She nods and hugs him.
“Thank you Katsu-nii!"
"It's not a problem." He hugs back. She shakes her head.
"I don't mean for clothes things! I mean everything!" She smiles. "You never left! And you never treated me bad!"
"Of course I stayed princess, you're my family aren't you?"
"Mhm!" She nods quickly and kisses his cheek.
"I don't mean to interrupt here. But what the fuck is going on?!" Kaminari speaks up. He’s the first to regain his speech after seeing Katsuki act so... not Katsuki like.
"Nii-san! He said a bad word."
"He did. And he shouldn't say that word again in front of you, should he?" Katsuki makes eye-contact with the electric boy. Kaminari gulps and nods.
"Got it."
"But I would also like to know how you know her Bakugo." Aizawa speaks up. "Since the only people she's interacted with before she came here were villains." Katsuki takes a deep breath, knowing what Aizawa is insinuating.
"No! Katsu-nii...Katsu-nii h-helped me!" Eri stands in front of him and holds her arms out. Katsuki can See she still struggles talking to him, it's understandable though. He's new to her and now she's disagreeing she will be more scared.
"Hey, it's okay." Katsuki puts a hand on her shoulder.
"No it's not okay!" She turns around quickly. "You're Not bad! You're like me!" She stomps her foot.
"They don't know that. They have to be careful."
"Not with you!" She shakes her head.
"The first time you saw me were you scared?"
"I didn't know you!"
"So you were scared." He raises an eyebrow, she nods sadly. "Exactly. And the first time you met me you asked me so many questions, do you remember?" She shakes her head. "Right you were very young. You asked me if I was safe, if I was going to hurt you, you asked me if I was bad like them."
"But you're not!"
"You know that now but you didn't before."
"So...they are just being careful? Not mean?"
"That's right." Katsuki nods. "They're Just looking out for themselves, making sure that they won't be hurt."
"I don't like it." She pouts. "I thought 'Zawa was good! And Deku! But they look at you bad!" Aizawa and Midoriya frown at this, why was such a simple thing affecting her so much? Katsuki knew they were confused but he wasn’t about to snitch. These are her issues to work through.
Since Katsuki was the first person to treat her well without any conditions she latched onto him. And he latched onto her. He wanted to protect her so he did his best. In turn Eri caught on and did the same. Eventually she found a few others to rely on, but she will always trust Katsuki the most. She will always be on his side.
"They are good.” Katsuki sighs, trying to explain in a way that makes her traumatised child brain understand... because his brain is so much better. “But are trying to protect themselves."
"Fine. I still don't like it! But they can ask questions." She crosses her arms and glares at Aizawa. "Don't hurt him! Hurt him and I'll hurt you!" The class are taken aback, it’s a completely different girl that was described to them, and a girl that none of them had met before. Even if Aizawa and Deku thought they knew her, they knew the girl who was too scared to stand up for herself. The one that Chisaki raised. The one they see now? That’s Eri who knows what she wants, that’s Eri who will fight for her rights. That’s the Eri that Katsuki raised.
"They're Not going to hurt me." Katsuki laughs and stands up.
"So, before you can ask questions I will explain myself. I however will ask that if anyone here exposes me I will be dead." He said the last sentence sternly, and it's a stark contrast to how he acted with Eri earlier.
"Dead as in...metaphorically?" Kirishima tries to joke, laughing awkwardly.
"Dead as in 6 foot under." Katsuki’s face turns cold.
"Fucking hell." And variants were heard throughout the classroom.
"I do need an explanation Bakugo or I will have to give you up to the police."
"Don't fucking touch him!" Eri grabs onto Katsuki's leg and growls. They had all heard her speak and that was a shock after being told she has hardly said a word to anyone, but now she's swearing and threatening a pro hero? What the fuck is going on?! Katsuki is glad she’ll stand up for him but this was his business. Aizawa tries to calm her down, but he’s using the method he would use for Chisaki’s Eri. And that won’t work here.
"I'm sorry Eri but if he's working with villains I-"
"HE'S NOT! HE'S LIKE ME! HE'S NOT BAD! HE'S NOT!" Eri shouts and balls her hands into fists.
"Eri!" Katsuki raises his voice, it's not shouting but he's strict and demands attention. "What did I say earlier?"
"He...he's Just being careful." She looks down.
"Exactly. So can you let me handle this please?"
"Promise you won't let them hurt you?"
"I promise." He nods. He then looks back at everyone.
"Okay. So put simply Mitsuki, my birth mother, sold me to the league of villains when I was 6. She was sick of my quirk and wanted me gone. I was only born to try and save my parents failing marriage." He sighs. "So obviously that didn't work and she sold me."
"But you were always at the same school as me?" Deku points out.
"They didn't wanna make it a big fucking deal so they kept everything basically the same. They trained me to be a villain and what not but," he sighs. "I never wanted that. I always wanted to be a hero. So I thought, fuck it, if I work with them I can gather information and take them down from the inside. So I managed to derail some of their attempts and got someone else to work with me."
"Nee-chan!" Eri smiles. "Is she okay?!" She gasps. "I haven't seen her in a long time!"
"Yes Princess, she's working very hard." He turns back to the class, "she's seen as just a ditzy girl it's easy for her to gather information. I've basically got another person working with me, we've got a deal." He shrugs. "I let him do his thing to one hero and he'll give me whatever info I need."
"So why come to UA?" Aizawa asks. He was confused, coming to the best hero school meant he had the highest rate of being caught.
"Multiple reasons. They let me come so I can take you down from the inside, which is ironic since I'm fucking doing it to them." He laughs. "And it means I am surrounded by heroes when it inevitably goes to shit."
"What does inevi- enevita-"
"Inevitably?"
"What does it mean?" Eri asks.
"It means that something will happen, it's unavoidable."
"Ohhhh okay." She nods.
"Have you got any proof?" Aizawa rubs his temple, god this fucking class.
"Stick me on a lie detector or some shit, I won't give you information if you don't trust me or I'll go down for it."
"Jesus Christ. I didn't know this was how today would work out." Aizawa sighs. "Sit the fuck down and I'll get you at the end of the day."
"So I'm not expelled?" Katsuki raises an eyebrow.
"Well if you're not helping the villains then I don't see why you would be." Aizawa sighs.
"Hell yeah!" Kirishima Stands up. "You've been helping us without us knowing bro! That's so manly!"
"I always thought you were mysterious, but not this mysterious." Sero laughs.
"Not anymore." Katsuki smirks and walks back to his seat. "All my secrets are out in the open. Well, apart from maybe a few." He shrugs. Aizawa glares. "They're Not big ones! Calm your ass down."
"Okay. Whatever. I don't care, it's time for your next class so I'll be leaving. Eri you need to leave too."
"No!" She shouts and runs to Katsuki's seat.
"I have to learn princess."
"Me too! I learn too!"
"Can't you go with Aizawa for the rest of lessons?"
"Nope!" She climbs him and eventually gets on his lap.
"Fine. You keep her." Aizawa rubs his temples and walks out.
"WHAT THE FUCK?!" Katsuki shouts.
"So Eri was it?" Kirishima looks at her and smiles. She nods. "Do you have any stories about Bakugo?"
"S-stories?" She thinks and nods. "I have soooo many!"
"Do you want to tell us a few?"
"No." Katsuki covers her mouth. Eri licks his hand and he lets go. "Gross."
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Maybe things would turn out okay. Eri was safe and for now he wasn’t expelled. Soon he’d had villains after him he was sure. But...he has help, both in the league and out.