Archive of Our Own ^beta

Chapter Text

He smiles. It makes his day. And that's when he knows he has to leave.

They've fallen into a routine, the lackadaisical day-by-day (at least on his sensei's end), and it's bad. It's the fact that it doesn't feel bad at all that makes it so bad.

He should have left the minute the apartment felt less like an apartment and more like home. Should have left the moment it became clear that Saitama really didn't have special techniques or secret training regiment.

He should have left the instant the hatred and revenge in his metaphorical heart began, bit by bit, to be replaced by…replaced by…

Replaced by…?

No. That was it. He had to leave. And the fact that the mere thought of leaving brought forth a pain he hadn't felt in years only made him more certain it had to happen.

...Tomorrow.

“Sensei.”

It's after dinner. Saitama is laid out on the floor, one arm propping his chin up, the other holding some manga, although the volume was slack in his hand as he watched the evening news. His eyes don't even leave the screen when he responds.

“What's up?”

“I think...” He pauses. Takes a breath he doesn't need. “I feel as if...”

He doesn't think. He doesn't feel. He knows.

So why can't he say it?

Saitama's attention is completely on him now. He's usually very straightforward with his words, perhaps a bit too straightforward at times, so this hesitation is strange. Genos isn't even looking him in the eyes like he normally does. He's in his usual position, sitting seiza near the wall, but there's a tension in his arms that…

That does what? Concerns him? Worries him? All Saitama knows is that whatever Genos is trying to say is not coming easy.

Genos abruptly squares his shoulders, and the words finally come out in a rush.

“I need to leave.”

Saitama raises an eyebrow. “That's it? That's what you wanted to say? Dude, you're free to leave, you know that, right?”

A strange look crosses the cyborg's face. He shakes his head slightly and clears his throat.

“What I mean is, it's time I moved on. I can't stay here any longer.”

“...Oh.” Saitama blinks. “Well, that's...”

He trails off. What? It's what? Okay? Not what he thought Genos meant?

Something he'd stopped considering a while ago?

“I've stayed here long enough. And while being your disciple has taught me many invaluable things, I feel as though I've strayed too far from my original path.”

The mad cyborg. Right. How could Saitama have forgotten? Perhaps because it had been so long since Genos had brought it up.

That, a distant part of Saitama's mind realized, was probably the issue. “...Right.”

“I apologize if this has upset you in any way--”

“No, no, it's fine.” Saitama waved a hand. “Like I said, you're free to leave any time you want, you don't owe me an explanation.”

“Thank you, sensei.” He bowed his head briefly, then resumed staring at the floor.

“When do you plan on leaving?”

The question forced its way out of his mouth, despite Saitama's best efforts to suppress it.

“...In the morning,” Genos replied, his voice quieter than usual. He suddenly stood up. “As a matter of fact, I should be getting my things ready. Excuse me, sensei.”

He walked out of the room without another word, and Saitama returned his gaze to the television, seeing but not really seeing at all.

Chapter Text

Genos had told the truth when he said he was leaving in the morning.

He'd just...neglected to mention how early in the morning.

It's 2:30 AM when he rises from his futon, careful not to disturb his sleeping sensei.

...Former sensei.

The pack he moved in with is already outside in front of the door. He'd moved it there while Saitama was taking a bath. One less thing to worry about.

He'd pretended to be asleep all night, getting up only when a quick scan of sen—Saitama's vitals showed that he was deep in slumber.

One less thing to worry about.

Or so he thinks.

He's halfway to the front door, an arm already extended towards the doorknob, when suddenly:

“So you were just going to leave without saying goodbye?”

If he was still fully human, the cold chill of dread down his spine would have been what rooted him to the spot. No, it's those eyes, ones he'd been too much of a coward to meet last night, that hold him frozen in place.

He doesn't need to turn around to read Saitama's mood. He doesn't even need to check his vitals. It's all in his voice. Saitama is pissed.

And for some reason, it irritates Genos as well.

“I just wanted to go without causing any trouble, sensei--”

“I thought you said you were leaving in the morning.”

There's an accusing note to his voice that Genos thinks shouldn't be there, and he can't help himself when he says, “It is morning, sensei, two thirty-six to be exact--”

“Don't be a smartass.” There's a rustle of sheets behind him as Saitama gets to his feet. “You know exactly what I mean. Just taking off in the middle of the night, that was your plan? I would just wake up and you would be gone, that's how you imagined it, right?”

Genos says nothing, just stares resolutely at the door. He'd been so close, this would have all been over--

“Can you at least look at me?”

Something burns in his chest. He doesn't know what it is, but it makes him spin on his heel, eyes narrowed, to face his former teacher.

“I don't understand why you're so upset,” he says in a low voice. “I just didn't want to bother you. That's all.”

“That's not all, and you aren't fooling me for a minute. You didn't want to face me. That's what it was.”

He's right, and Saitama knows he's right when that yellow-eyed gaze once again drops to the floor.

“Why?” Saitama demands. And they both know that it isn't just a “why are you leaving without saying goodbye”, it's why are you leaving that's the real question here.

At this Genos's head snaps up, a faintly sardonic look in his eyes. “I thought you said I didn't owe you an explanation.”

There's a brief silence, during which Saitama's mouth opens and closes without saying a single word. So Genos talks some more.

“You acted like it didn't bother you that I was leaving. You said I was free to leave. And now you're standing here telegraphing the exact opposite.”

Saitama isn't expecting that at all, and he realizes Genos has a point. He'd acted like he didn't care, acted as if all Genos was doing was taking a walk around town.

Before he can even attempt to explain himself, however, Genos starts talking again, and there's an emotion in his voice that Saitama can't place.

Or maybe he just can't bring himself to place it.

“But, okay. If you really want to know why I'm leaving, it's this.” He makes a gesture with his hand, back and forth, between himself and Saitama. “This right here. I'm leaving because I have to. And I can explain that, too, but”--he allows himself a bittersweet smile-- “it's going to take more than twenty words.”

Saitama has to swallow past a sudden lump in his throat, but he finally finds the words to speak. “...Go ahead.”

“Before I met you, when it was just myself and Dr. Kuseno, I didn't have a place that really felt like home. More often than not I wandered through city after city, chasing any possible lead on the cyborg who'd taken my family, my actual home, away from me. On the rare occasions I slowed down long enough to sleep, in my dreams I still chased that figure, one who was quickly becoming nothing more than a ghost of my past.”

Genos looks down, away from Saitama.

“Dr. Kuseno is a kind man, and I owe him my very life, but...aside from repairs and upgrades, I never really saw his place as somewhere to establish roots. How could I, when at any moment that cyborg could be destroying another town, taking more lives? I promised myself that I would not settle down, would not make another place my home until I’d found that monster and eradicated him, along with anyone who tried to get in my way.”

He smiles again, the same bittersweet one, and shakes his head.

“And then I met you, sensei.”

Saitama wants to say something, anything. But he doesn’t exactly trust his mouth right now, so he just nods.

“At first, I just wanted to discover the secret to your strength. Whatever it took to get as strong as you, I would do it, and then I would go find and defeat the cyborg, just as I’d sworn to do. But that secret was proving elusive, and I found myself spending far more time studying you than I intended. Whatever it takes, I told myself, trying to justify it. Register as an official hero? Sure. Move in with you? Done.

“But...” Genos lets out a breath. “I...after a while, I stopped trying to convince myself that I was here because I had to be. That just wasn’t the case anymore. I was here because I wanted to be. I was staying because I liked being here—having someone to interact with on a daily basis, besides the good doctor—it was...nice. For a while, I didn’t want to admit it, but having to focus on something that wasn’t revenge felt really good. Having a place to come back to, it was...I was...”

He drifts off, and Saitama comes to a realization.

“Genos,” he says, his voice low, “you were happy. That’s what you’re trying to say, right? I get that you must not have known how to deal with that, but it doesn’t mean you have to leave--”

“But it does, Saitama,” Genos says quietly, and the absence of the usual honorific hangs in the air, almost tangible. “It’s selfish, staying here any longer when I know, at this point in time, I know there isn’t any kind of strength training I can learn from you. How can I be happy when that—monster has been roaming free, doing god knows what, and I’ve just been here--”

“Saving people. You’ve been saving people, Genos, it’s not like you’ve been laying around doing nothing.”

“They don’t need me, Saitama. They have you.”

“That’s not--”

“And it's not like I need to be here to help people. The Hero Association can always call.”

Genos pauses.

“Besides...I feel that Z-City is safe in your hands. You...you’re more of a hero than I’ll ever be.”

Silence.

It’s not what he really wanted to say. Not even close. But it’s the best he can do, turning his back on Saitama once again, and that weird burning feeling once again taking up residence in his chest.

...If he didn’t know any better, he’d say it felt like heartbreak.

But that was absurd. He didn’t have a heart.

He didn’t have a heart.

So why--

“Genos.” There’s a flatness to Saitama’s voice now, and Genos will not scan him, he will not; he doesn’t want to know if his vitals match his tone, doesn’t want to know if Saitama has figured out the real reason why he can’t stay another day, doesn’t want to see his face, doesn’t want--

“Is this really what you want?”

No.

No.

“Yes.”

A long silence follows this, a silence so loud it hurts, and then Saitama turns away. Genos feels rather than sees it happen, and for some reason it’s this action above all others that triggers a mad sort of desperation within his mind.

Turn back around. Please. Turn back around, tell me you know I’m lying, tell me to stay--

“...Well, if that’s the case, I’m not going to stop you. It’s your choice. Do what you want.”

That phantom pain, that heartbreak is reaching a fever pitch, and Genos can’t even blame it on Saitama’s words, no, it’s all him, this is all his doing, he’s breaking his own heart that isn’t even fucking there--

“Thank you.”

“Uh-huh.” A rustling of covers, and Saitama is back in his futon.

Genos is still for about a second more before he grabs the doorknob and pulls the door open. There’s a light wind blowing outside, and it ruffles his bangs.

He’s not going to look back.

He won’t.

Tell me to stay.

Tell me to stay.

Then, quiet as the wind in the night, he hears it:

“...Bye, Genos.”

Was he supposed to hear that? Saitama knows Genos has excellent hearing. He must have known he’d be able to hear it.

Genos finds himself biting his lip. It’s an old habit from before he became a cyborg. He knows what it means, and that only makes him bite down harder.

He doesn’t want to go. He doesn’t want to go.

But he has to.

“Goodbye, Saitama.”

Chapter Text

There’s finger indentations on the doorknob.

That should have been the first clue, but Saitama has never been a particularly observant person, and besides, there was always the chance he’d accidentally done it himself; he always tried to be mindful of his strength, but there were still some times where he’d slip up and break something.

...Like the time he’d meant to pull Genos out of the rock that little green terror had smashed him into after the whole Boros thing, and wound up tearing his arm off. He’d apologized, of course, but there was something in the way Genos had just closed his eyes in response that had him fighting back laughter and--

Anyway. Who knows how long those finger marks have been there. Who knows how they got there? He could have just done it himself and not even realized.

That’s probably what happened.

That’s what he tells himself.

(He doesn’t get a new doorknob.)

(And he is very careful not to make any new dents.)

He’s been having a hard time sleeping lately.

Honestly, this would have been a bigger clue than the doorknob if it weren’t for the fact that Saitama is no stranger to sleeping problems, so it takes a while for him to pin down the reason for this particular bout of restless nights.

He does figure it out eventually, though.

The apartment is too quiet.

And the apartment is just a little too cold.

It makes him a little mad, actually; it wasn’t like he’d slept with a fan on or anything before Genos moved in, so why was it that the absence of that stupid little whirrrrrr sound Genos’ fans (processors? whatever) made was enough to keep him awake at night?

More importantly, why had he let himself become so used to that sound? When did it become such a constant in his life?

And the cold. It’s absolutely ridiculous. He’d gone months without heat as part of his training regiment, and he’d made it through the night just fine. There was no reason a change in temperature this slight should be affecting him the way it is.

…Maybe it’s what that particular warmth meant, what it signified: a body next to his; one who, despite Saitama’s claims that he didn’t need a heater (usually said while buried underneath extra blankets), always managed to get the small room to the exact temperature needed to stop Saitama’s shivering.

...Who hadn’t said a word when Saitama, deep in slumber, had rolled over one night and slung an arm around his torso, subconsciously scooting closer to that warmth.

Who, the next night, had placed his futon just a little closer to Saitama’s, making it so he didn’t have to roll too far to put his arm around him again and--

Anyway. He’s just going to have to re-adjust, that’s all. No big deal.

(It’s a bigger deal than he anticipates.)

(The restless nights continue.)

The curry tastes different, and this time Saitama really can’t figure out why, and it’s here that he finally slips up.

Because he forgets, and he forgets just long enough to poke his head through the little kitchen window, eyes still trained on the stove, and ask, “Hey, Genos, what’d you put in the curry last t--”

He breaks off, eyes swinging around to the empty living room, and he remembers.

Remembers that he’d meant to ask Genos about the curry the very first time he made it, but had gotten distracted by the television blaring a sudden news report about a demon-level monster sighting in downtown City J.

He’d wanted to know so he could make it himself, in the event that he had a taste for it and Genos wasn’t home, due to repairs or his S-Class hero duties or--

Or…

Damn it--

An acrid smell forces Saitama’s attention back through the window and on his dinner. He hastily stirs the curry, pointedly ignoring the dents he’s made in the wooden spoon.

(He only burns the curry a little. It tastes just fine, really.)

(It doesn’t taste the same at all.)

It’s absurd, honestly. It’s not like Saitama doesn’t have other people to hang out with.

He chooses to ignore the fact that in a way, he wouldn’t have other people to talk to if it weren’t for Genos.

What isn’t as easily ignored, however, is the look King keeps giving him from the corner of his eye as the two sit in his apartment, playing the fighting game King had recently purchased.

“...Are you all right, Saitama?” King asks after three of these not-so-discreet glances.

“I’m fine,” Saitama bites out, trying with all his might not to get caught in another one of King’s ridiculous combo attacks. He can (just barely) tolerate getting his virtual ass kicked, but for it to happen for five straight minutes is more than he can deal with.

Silence once again falls between them, save for the clicking of controller buttons and the occasional sucking of Saitama’s teeth.

“Are you sure?”

Saitama can hear it now, the bass drum beat of King’s “roaring engine”, starting off slow but gaining in both volume and tempo.

He’s nervous, and it only serves to irritate Saitama further. King has nothing to be nervous about, he is fine, he’s just fine--

“Yeah, I’m sure, man. I’m fine.” His tone is more easygoing, nowhere near as harsh this time, and he thinks he’s finally convinced King to drop the subject. Those glances stop coming his way, and there’s a bit more fluidity in the curb-stomping of Saitama’s character.

...And then King, eyes firmly focused on the screen, says, “Well, you’ve been sort of tense ever since Genos moved out and--”

Three things happen at once: King’s character finishes off his ultimate move, the game’s voice-over shouts “K.O!” and Saitama snaps his controller in half.

(...Well, almost at once.)

(The breaking of the controller comes just a little too early to blame it on Saitama losing the match.)

(Saitama pretends that’s what caused it anyway.)

(King decides not to let on that he knows Saitama’s lying. After all, he did offer to replace the controller.)

Mumen Rider, Saitama realizes, is a goddamn saint.

He always has people’s best interests at heart.

He’s probably never hurt a single soul in his life. At least, not intentionally.

So when he invites Saitama out for drinks, Saitama accepts. What’s the harm? Just two friends hanging out together.

(Never mind what happened last time he hung out with a friend.)

They’re at the bar, Saitama nursing his third drink while Mumen idly swirls the ice cubes in his own.

The clink, clink of the ice is rather soothing, actually. It distracts Saitama from his thoughts, and he closes his eyes, letting everything fade away except for the chime-like sounds of the slowly melting ice. He takes another sip of his drink, the alcohol leaving behind a pleasant buzz.

His eyes are closed, so he can’t see Mumen sit up straighter in his seat. He just barely hears Mumen’s sudden inhale and exhale, as if he’s preparing himself for something big.

He takes another sip from his glass just as Mumen asks, “Did you and Genos have a fight or something?”

His jaw snaps shut just in time to prevent him spitting his drink across the bar, and he starts coughing instead. Mumen hastily pats him on the back, murmuring thanks to the bartender as he wordlessly slides over a glass of water.

“Are you okay?! I’m sorry, I didn’t mean to--”

Saitama waves him off. “No, no, it’s all right, I’m okay.” He rubs his nose, pausing a bit before asking, “Um...what makes you ask if we had a fight?”

He hopes the answer isn’t his body language, he’s been trying not to make it so obvious, especially after what King said, but trying to hide emotions he’s not used to feeling is harder than he thought it would be--

Anyway. Mumen looks fairly apprehensive now, as if he knows Saitama’s not going to like his answer.

“...I ran into him the other day.”

Mumen has gone back to swirling the ice in his glass, a bit faster now, and so neither of them hear the sound of a hairline crack forming in the glass in Saitama’s hand.

Mumen Rider is always going out on patrols. It makes sense that he and Genos would eventually cross paths.

(Saitama has also taken to going out on patrol more often lately. He hasn’t seen Genos once.)

(He tells himself it doesn’t mean anything.)

“He looked kinda down about something. Well, I mean, it’s a bit hard to tell when he always seems to be frowning, but there was something different about it this time, you know? So I asked if he was okay, and it took him a little too long to say yes.”

Mumen takes a sip from his glass. Distantly, Saitama thinks that it can’t possibly taste very good anymore, the ice has almost completely melted.

“I just figured that maybe the two of you had an argument about something.”

Saitama can’t quite figure out how Mumen made that connection, and it must show in his face, because the bicyclist shrugs and adds, “Genos and I don’t talk much, but the few times I’ve seen him look anything close to happy, he was with you. And when I asked him where you were, he just...didn’t answer. Said he had to go and hurried off. So I assumed his mood had something to do with you.”

Saitama doesn’t really hear the end of Mumen’s explanation. All he can hear, over and over, is the few times I’ve seen him look anything close to happy, he was with you.

He was with you.

The glass shatters in Saitama’s hand, startling Mumen once again. The rider for justice grabs some nearby napkins, apologizing profusely.

Fuck, Saitama thinks, fuck, and he’s not even sure what he’s cursing, his brief loss of composure or himself for being such an idiot--

(They leave the bar shortly afterwards, Mumen still apologizing, saying he wished he hadn’t brought it up.)

(Saitama forgives him, tells him it’s no big deal. Mumen Rider, after all, is a goddamn saint. He’s probably never hurt a single soul in his life.)

(At least, not intentionally.)

The person who winds up getting to him the most, however, is someone who most likely has years of experience in hurting people.

Saitama’s in front of his apartment, taking out the garbage, when he hears the tell-tale shing of his fairly amusing, fairly annoying, so-called “rival” unsheathing his katana.

“I’ve come to challenge you again, Saitama! And this time I will defeat y--”

Saitama doesn’t even bother turning to face him.

“Listen, Panic, can we do this some other time? I really don’t feel like playing with you right now.”

There’s silence for a couple of beats, and Saitama can practically feel the waves of anger radiating off the ninja behind him.

“It’s Speed-o-Sound Sonic, and I’ll show you just how playful I am!”

Saitama lets out a sigh, and turns around, effortlessly catching the blade as it slices through the air towards his face. He stares blankly at the enraged face before him.

“Like I said, man, I’m really not in the mood right now. Why don’t you come back later, I’ll fight you properly then. Just not now.”

Sonic regards him warily for a moment, then raises an eyebrow as Saitama releases his sword. “Fine. If you won’t take me seriously, I’ll just come back when you do,” he states. “What’s your problem, anyway?”

“None of your business.” Saitama begins to walk away, back towards his apartment. “See you later, I guess--”

“Wait a minute.”

Saitama looks behind him. Sonic is frowning, arms crossed, like something’s out of place and he’s trying to remember what it is.

“Where’s your little lapdog? That guy, the Demon Cyborg. Where is he?”

Saitama clenches his jaw, takes a breath in and out through his nose before he answers. “He’s not my lapdog. And he’s not here. He moved out.”

He thinks he sounded nonchalant, but clearly that isn’t the case, because Sonic lets out a bark of a laugh before pointing at Saitama.

“That’s it, isn’t it? That’s why you’re upset! You don’t have your little fanboy to order around anymore, that’s why you’re so down?”

Saitama’s right hand curls into a fist, and he keeps his eyes fixed on his apartment door, taking another slow breath.

“He’s not my fanboy, and that’s not--”

But Sonic is still laughing, still derisive, as he doubles over in mirth.

“Oh, man, you’ve gotta be kidding me. If I were you, Saitama, I’d be relieved to be free of that clingy shithe--”

Saitama turns on his heel and punches him.

And it’s a true testament to how messed up he is right now, because he misses, the shot going wide, past Sonic’s face.

...Not that it really matters, though. The force behind the swing of his fist is more than enough to send Sonic flying through the building across the street and into the one behind it.

For a while there’s nothing but the sound of concrete cracking and glass shattering, falling to the ground. Saitama pauses, and it’s not until he hears Sonic shouting something in the distance that he heads back to his apartment.

He told him he wasn’t in the mood.

Saitama grabs the doorknob to pull open the door, when he realizes he’s using more force than he needs to. He lets go of the knob, and sucks in a breath, not wanting to see what he knows will be there.

There’s finger indentations in the doorknob.

And they don’t match the ones on the knob on the inside of the door.

Saitama rests his forehead against the door, closing his eyes for a brief moment. The moment passes, and he finally opens the door, stepping into the hallway and leaning against the wall.

(He still doesn't get a new doorknob.)

(And he is still very careful not to make any new dents.)