Chapter Text
Z-city's ghost town seemed to be utterly shaking.
There was no sign of life there, though. Well, except for two humanoid shapes moving so fast they were more of a blur, really. Seen from a distance, they seemed to flicker together in a choreography that was almost a dance. They were getting close, touching, separating, swirling around each other in light and dark flashes, wind going wild around them.
Each fall made the earth rumble. Each landing made asphalt crack. Each launch off a building left a concrete fissure. Steel protested, glass exploded, stone collapsed.
And in the midst of this cacophony, sometimes actual laughters could be heard.
Both Saitamas had realized they were able to hurt each other. That had changed the very nature of their fight. The first bloodshed had awakened something feral inside of them, something that had been buried deep down since the end of their training.
Something curious, excited, determined.
Something fun.
So, they had started to take more space. Their close quarters duel had taken on a grander scale - partly because they were both letting their imagination run wild in this oh so long awaited battle. The Saitama of this world hadn’t been able to suppress a surprised grin while dodging a whole fleet of thrown cars raining down on his position. The Saitama of the portal had genuinely laughed out loud while deflecting a lamp post bent like a boomerang that had been thrown at his neck.
Mostly because they both hoped they could strike a major blow whilst staying out of reach. In their long-range attempts to distract the other or to evade attention, both Saitamas were struggling to get an advantage over the other, either through the element of surprise or by gaining momentum for more powerful blows - blows that were systematically dodged or repelled by their opponent. No fresh scratch was added to those received in the first assault.
The only fallout from this tactical change was the destruction of the district around them. Here, water was spraying from a pipe that had burst; there, dust was settling from a building that had collapsed. But, all in all, the damages remained limited. Both Saitamas were holding back. Z-City was still standing, wasn’t it?
***
Unsurprisingly, this relative chaos ended up attracting someone.
And that someone had to be Mumen Rider.
He was finishing up his patrol in the city center when he heard a distant, ominous echo. He felt the ground tremble under his feet. And Mumen Rider, being the hero he was, didn’t think twice before riding his bicycle of justice towards the source of the commotion.
He stopped a few meters after entering the ghost town to analyze the situation. The end of the street was plunged into a cloud of dust, through which he could make out the faint outline of a pile of debris. Overhead, black smoke was rising to meet the horizon. Yet, despite all the wreckage, the area was dead calm.
A flash of yellow drew his eyes to the top of a nearby building. He had no time to take a closer look: out of nowhere, Saitama had materialized in front of him. Where the pavement had been intact a moment before, it was now split in half.
“… H-Hi!” Mumen greeted in a gasp.
“Yo. Mumen Rider, right?” asked the other hero. Saitama was observing him carefully, eyebrows slightly frowned, almost out of breath. His yellow outfit was scratched in some places. Some blood had dried under his left nostril. When Mumen nodded, he spoke again in a hurried tone: “You have to leave.”
“What’s going on? It’s a mess out here! Are you fighting a monster?”
The bald man let out a short laugh.
“You could say that. A kinda strong one.”
Was he… amused?
“Then you need all the help you can get,” Mumen said firmly. “I’m staying.”
Saitama’s face hardened again, and he examined the streets and the sky suspiciously.
Nervously.
“That’s nice of you, but I’m serious. Leave now. No offense, but you’re no match for this.”
Mumen Rider followed his gaze. Nothing seemed to be coming. Everything was silent around them. What exactly was he fighting?
He was about to ask Saitama when he felt a pressure on his stomach take his breath away. In the blink of an eye, he found himself across the street. He would have lost his balance if not for the other hero’s support, who waited for him to get his footing before letting go. Mumen turned to see the place where they stood a moment ago. The sidewalk had been pulverized by a crater, in which someone was straightening up – wait, not just someone –
“ Wha-?!”
“Go.” Saitama’s voice had regained its calm.
Mumen Rider’s gaze lifted from the silhouette that was facing them to the hero standing next to him. Saitama was looking at his – his opponent intensely, as if to prevent him from sliding out of his sight again. His features reflected intense concentration… and… was that the hint of a smile?
But who on Earth was th–
The other took a step forward, and Saitama charged him, both of them meeting a few meters away from Mumen Rider. The resulting shock rattled the C-class hero to his bones. He had little choice but to take his bicycle and leave.
He didn’t look back.
There was one thing he understood about what was going on, and that was that he was no match.
***
Saitama gave a satisfied nod when he saw Mumen Rider leave the combat zone. He could try and keep their fight further away; since it had begun, he had been carefully keeping the action confined to the far side of the ghost town, as far as possible from the inhabited parts of Z-city. But he was sure the only reason why his efforts were paying off was because the other let him do so. If he had wanted to attack Mumen Rider while he was still close, Saitama might have been unable to stop him. Now that the C-class hero had gone, the other would, at least, have trouble trying to find him. That was something.
He allowed himself to let out a relieved sigh before turning his attention back to his opponent. Their face-off had led them two streets further, where he had managed to escape an uncomfortable grip to take his distances. Once more, the other paused, a few meters away from him.
And, once more, he broke the silence.
“So! Standing up for your coworkers?” he asked in a light tone. When Saitama didn’t react, he went on. “The dude never really helped much, though.”
“Mumen Rider is a good man,” he answered with a shrug.
The other raised an eyebrow.
“Yeah, guess you’re right. So what?”
“So what?”
“Since when does that matter? There are a bunch of good people. That doesn’t mean you’d lift even a finger for them.”
Saitama felt honestly confused.
“I don’t know what you are talking about.”
The other sneered.
“Come on, don’t tell me you’d have protected the number one brat, had she been there.”
“The brat…?”
“Yeah, y’know, the lil’ girl with green hair. The one who flies. S-class, rank 1.”
Saitama scratched his skull thoughtfully.
“I don’t really pay attention to all that ranking stuff, but I’m pretty sure she’s second. The first one’s a dude, from what I heard. Never saw him.”
The other him frowned.
“A dude…? I would have known… I know them all.”
What was that supposed to mean? Saitama didn’t have a clue. The other was deep in thought, mumbling to himself.
“He’d have escaped me? … No, nothing of the sort was in the hero catalogue...”
Then, turning his attention back on Saitama, he asked aloud, “What did you say his name was?”
“I didn’t. I dunno.”
The other swore, then resumed his grumbling: “And I thought… but no… the last hero in the world…”
A very bad feeling washed over Saitama. Voice sharp, he snapped: “What happened to your world?”
“… my world?”
His double’s face scowled even more under an obvious effort to process some thoughts. Then it lit up.
“Maybe… yes… not another time… but another place…”
He had just understood something of importance, that much was clear. As for the hero, he was still wading through complete ignorance. He was getting impatient.
“What the fuck are you talking about?”
“I thought… - I went through a… portal, to get here” he started, eyes wide open, unfocused. “I thought… I believed it had taken me back in time. To several months ago, from the city’s general state. But what if… what if I were wrong?”
He made a motion to the damaged area around them.
“What if all of this was part of another world? Another… dimension?”
Saitama didn’t react to the hypothesis. Not physically, at least. Questions were jostling in his mind, each less sensible than the next. Was the other him coming from some kind of… parallel universe? Alternative reality? Was that even possible? It sounded like movie crap. But it would explain the similarities he shared with his double.
The guy was still talking.
“But everything looks so identical… Unless… this strange feeling back in the town… in the apartment… and Tatsumaki… yeah… that’d explain a lot of things.”
“You didn’t answer my question.”
Saitama’s voice had snapped, serious, sharp. It abruptly tore the other away from his meditation, causing him to almost jump out of surprise.
“What happened to your world?”
A silence fell between them. So heavy Saitama could feel its weight on his shoulders. So intense he found himself out of breath.
They stared at each other like this, tense, unmoving, for a while. Then, without the faintest emotion on his face, the other started talking in a monotonous voice.
He talked about training, triumph, power. About weariness, boredom, indifference. About feeling empty. Depressed. Alone.
Then he got excited, and his voice warmed up. He talked about an idea, an impulse, a purpose. He talked about a plan he had imagined, applied with care, made last a little longer by playing around. He enthusiastically painted a picture black as death, and red as blood.
Saitama refused to believe it.
… wished he didn’t believe it.
As the other talked, Saitama’s face turned paler and paler. No, this wasn’t true. This couldn’t be true. If the other was like him in the slightest, nothing of the sort could have happened.
But he had no doubt that it had. And despite everything, they were a lot alike.
The other’s speech made him feel sick. It was revolting, unthinkable. And yet… vaguely familiar. Saitama couldn’t deny he had been bored, too. He had felt isolated. Maybe still did, sometimes.
Dark thoughts he had been containing deep in his mind threatened to come to the surface. He shook his head as if to chase them away.
I’m not like him. I’m not him.
The other was still speaking, seemingly more to himself than to the hero. He was lingering on details, names, places. Suddenly it all made Saitama feel ill. It had to end.
“Do you ever shut up?” he interrupted.
The other went quiet, sending him a sharp glare.
“What I understand is you’re a crazy bastard. But you didn’t come here to chat, right?” Saitama grinned, but there wasn’t any humor in it.
The other forced out a laugh.
“Well said! I’ve never been the talkative type anyway. So, sweetheart, shall we go on?”
The fist that aimed for his jaw was quite a clear answer.
The fight started over, the ground resumed trembling, buildings resumed resonating with the sound of destruction.
But something had changed.
No laughter could be heard.
There was no time left for fantasies or provocations.
This time, things had gotten personal.
***
Genos hadn’t expected to find Z-city’s ghost town in such a state.
He had unsurprisingly dealt with the monster attack in C-city efficiently. The demon level threat had put up some resistance, but had hardly been a real danger to the cyborg. He hadn’t lost any limbs. Even his sleeveless shirt had remained untouched.
He had planned to get some groceries on his way back, but had frozen at the sight of columns of thick, black smoke rising from the area he was living in with Saitama in the distance. That was unusual. He had jumped from one building to another to get closer and have a better look at the place, and had noted the ruins that were scattered in that zone.
His sensei would never have let the neighborhood get that damaged.
After a short reflection, the cyborg had formed two theories. Either Saitama hadn’t intervened because he hadn’t been aware of the situation - he could have left the apartment while Genos had been away to attend a timed sale perhaps, even though none were advertised for today, or...
… Or his sensei was there, but was facing something he couldn’t contain.
Genos frowned at that. Everything was so quiet. Nothing that would let one think –
His eyes caught a movement a few streets further, as a building crumbled noisily.
Genos rushed in without thinking.
By the time he arrived, nothing was moving anymore. The street was empty. Yet he could hear the sounds of battle nearby. He followed them, but couldn’t pinpoint their origin.
No matter how fast he was, the fight that was clearly still raging was constantly just out of reach. He couldn’t even see the combatants. But he could hear the muffled noise of exchanged blows and the clatter of debris flung in all directions; he could feel the shockwaves of collisions and the tremors of landslides. He was close, so close…
Then, all went quiet again.
Genos arrived in a hurry to their last known position, according to his sensors. A cloud of dust was slowly dissipating, revealing a mound of rubble. There, slumped on the ground, sitting against the remains of a wall he appeared to have been flung into was..
… Saitama-sensei?
Genos froze, eyes wide, mouth ajar. He’d never seen his sensei in such a state before. He seemed… exhausted. Shoulders low, head down, one hand weakly resting on his bent knee. He didn’t show any signs of getting up soon. But he did lift his chin up, and met his gaze.
Saitama didn’t seem surprised to see him. He wore a tense, irritated expression. In his eyes, a furious gleam vaguely mixed with something akin to… worry?
And all this blood… abundantly flowing from a freshly opened wound on his forehead –
“Sensei!” shouted Genos anxiously as soon as his words found their way back to his lips.
“… sensei?” repeated a voice behind his back.
A cold, sinuous, utterly strange, yet familiar voice.
Genos turned abruptly, his body adopting a defensive posture, to face the man who had spoken. The man who was approaching.
This is not Saitama-sensei, his instinct immediately screamed at him. Odd, when the physical similarities were so obvious; but just as soon as the cyborg had recognized the features of his face and the lines of his silhouette, he had perceived what made him different. The costume. The dark circles. The look. The attitude –
“I don’t have you in my universe”, said the man darkly.
Everything in this silhouette inspired mistrust, radiated threat. Whoever the stranger was, he was the cause of his sensei’s bad condition. He, too, was bearing the marks of the battle: some blood had leaked from his lower lip, scratches and cuts were scattered across his cheekbones and skull; but all in all, he appeared to be in a better shape than Saitama. In a flash, Genos straightened, preparing for a fight. When he opened his mouth, it was to shout a fervent cry.
“I am Saitama-sensei’s loyal disciple! I would do anything for him!”
The stranger arched a brow out of disdain. And confusion.
“Anything? Why?”
In a flash, he was there, his face a few inches apart from the cyborg’s, his hand tight around his neck in an inescapable grip. Under the pressure, the plate of his jaw cracked.
“What makes you so special?” he asked, low, staring.
Unable to move, or even to look away, Genos could only gasp as he felt a hand brutally force open the plates of his torso, reach inside his chest, and seize the warm, vibrating sphere that was there. The core,suddenly ripped out of his body, flooded the area with a bluish light, highlighting the expression of his aggressor, accentuating the shadows of his frowned brows, reflecting on his clenched teeth.
“Are you the reason why this Saitama is still good?”
A ghost pain ran through Genos’ entire body. His energy levels were dropping at an alarming rate. By reflex, he loosely grabbed the fingers still stuck in his throat, but he knew very well any attempt at resistance was futile.
So he studied the other. His captor had eventually let his eyes slide down to stare intently at the now vulnerable core. His features had slightly softened. His gaze was lost in contemplation. He seemed almost… hypnotized.
Behind the cyborg came his sensei’s voice, stern, biting:
“Let him go!”
If the other had heard, he didn’t let it show. Caught in his observation, he applied a pressure, maybe involuntary, on the core, which began to crack with a sound of broken glass.
“Oi! Bastard!” shouted Saitama.
The other seemed like he had entered some kind of trance, as if carried away by memories that isolated him from the outside world. On his face were jostling shadows of past emotions, as if brought back to life.
The cyborg was striving to stay conscious, and, in that very instant, through barely open eyelashes, the differences between his aggressor and his sensei became more obvious than ever.
That clenched jaw was more emaciated than the one of the Saitama he knew. That forehead more creased with anxiety. Those lids more marked by fatigue.
Right then, perhaps from the proximity, perhaps from the contact of the other’s hand with his fractured core, Genos felt close to him, in an inexplicable, ineffable way.
The other glanced up in stupor to meet his gaze. The cyborg was struggling to form coherent thoughts, and, feeling himself gradually slip into the void, was desperately fighting to stay awake, but he could sense the aura that was coming off his opponent. He could read it in the tension of his shoulders, the sadness of his expression, the absolute black of his pupils.
He was lonely.
A wave of understanding washed over him and seemed to hit the other, pulling him out of his thoughts, leaving him dazed. He gave his double an astonished look. An envious look.
“What did you do?” he breathed, his attention back at Genos. “… that made it so different?”
The cyborg’s throat could not technically burn from the violence of the grip or from the lack of oxygen. His vocal chords hadn’t received any damage. His voice was hoarse nonetheless.
“I… I care about him.”
At those words, the other flinched as if he had been hit. He took a step back, releasing Genos’ neck and leaving him to flounder. His attitude became less threatening, and more offended.
“Where were you in my universe?!” he accused, rage in his posture.
One second later, an invisible force had thrown him several meters away.
***
Saitama had stayed leaning against the wall for a time that had seemed painfully long.
Endless.
After crashing onto the building, he hadn’t immediately got up. He had needed a break. Goddamnit, in those last attacks, the other had begun to take the upper hand, and he had felt exhausted. And even more pissed off. His double and him had both been on the edge since their little… talk.
Then Genos had showed up. There was nothing surprising in that. It would have happened eventually, one way or another: the C-city monster couldn’t keep him away for long, and he wasn’t the type to stay wisely out of trouble, especially not when his bloody sensei was involved.
That was why Saitama hadn’t even tried to send him away. The only thing that would have accomplished would be making Genos curious. He would have asked a thousand questions, and Saitama couldn’t afford to let himself lose his focus.
Well, not like it had kept the other from making a mess anyway. Saitama had suspiciously watched him getting closer, had hesitated to intervene. For a moment, he’d thought that, even in his universe, the other couldn’t have harmed Genos. That he wouldn’t go as far as to lay a hand on this one. Wrong. Stupidly, critically wrong.
When his asshole of a double had torn his disciple’s chest open, when he had ripped out his heart, Saitama had no longer dared to move.
He didn’t know a thing about robotics. He didn’t know if Genos really was in more danger than the hundreds of times his body had been dislocated or cut in half. He had no idea as to the consequences that damage to his heart could have – could this even be called a heart?
But he had no intention of discovering it.
And he had feared that, at the slightest movement on his part, the other would have a dangerous reaction, voluntary or not. After all, he held Genos’ core in the very palm of his hand. Out of spite, out of curiosity, perhaps out of surprise, he could so easily –
For the second time that day, Saitama had mentally shaken his head to clear his mind. He’d decided to stay still to avoid any risk that the other might cause irreversible damage to his disciple. But he had stayed on the lookout for the slightest opening in his behavior. The slightest flaw. The slightest weakness.
He had focused his attention on their… conversation for a long moment, but he hadn’t been able to keep from uselessly shouting at his double. He had forced himself to keep calm despite the awful sound of his disciple’s heart creaking and cracking in the claws of the other. Let this bastard give him an opportunity to intervene, just one! He wouldn’t miss it.
He finally noticed a change in the other’s attitude. While – speaking with Genos, he had become progressively unsettled; right now, he seemed on the verge of letting go of him. He was staggering. The hero was ready.
The other took a step back. His left hand released his grip. His fingers loosened around the sphere –
Saitama was already there. With one precise, calculated gesture, he took the core from the other’s palm to secure it in his own hand, then pushed his foot in the ribs of his double, who went crashing into a building at the end of the street.
The hero took advantage of the short respite he had just offered himself to support Genos and carefully replace his heart in his wide open chest. He roughly straightened one of the deformed plates to cover it. It wasn’t ideal, but it would have to do for now. He eased his disciple down onto the pavement, then spotted his double who was laboriously getting up, and rushed to him with a newfound energy.
The whole operation hadn’t lasted more than a handful of seconds, and Saitama had regained control over the situation. Now he had to put as much distance as possible between Genos and his double. He had to give the cyborg enough time to recover and move away, maybe go to the lab, if he felt strong enough. He would find him back later.
Meanwhile, he had a mad son of a bitch to put in his place.
Who, this time, stunned by surprise, slowed down by painful ribs, battered by the hero’s relentless attacks, no longer seemed to show off.
Despite the anguish that had gripped him earlier, despite the tension that still stiffened him, despite his wounds and bruises, Saitama suppressed a feral grin.