Genos fell for Saitama quickly. So hard and so fast it blindsided him. All it took, ironically, was one punch. Everything after that -sensei's kindness and humility, everything about him really- cemented the feeling, and he fell further the longer he stayed with his sensei. He even found himself adoring sensei's worst habits despite himself. The more he came to know, the more he came to love.
Saitama fell for Genos more slowly. He'd never truly disliked the cyborg, but at first he'd seemed like a nuisance. A nuisance who talked way too much. Despite his promise of twenty words or less Genos still rambled on fairly often (he was pretty sure Genos could create a long-winded speech about almost anything at this point). Saitama found himself minding less and less. He's still a little guilty that at first he hadn't cared about the young cyborg all that much. It didn't occur to him how... breakable Genos was, back then, how warm he was, how bright and brilliant. Strong, perhaps stronger than Saitama himself though in a different way. He'd done what he could to protect Genos, in the beginning, but now it was... just... different. The cyborg was a permanent fixture. Saitama couldn't really imagine life without him, and he certainly didn't want to. Having him around didn't magically make things better -it was irrational to think their relationship could instantly fix all the problems that followed Saitama around- but Genos made him happy. Happier than he'd been since... ever, really. Things finally felt like they were looking up; Saitama felt like he was moving forward again. Slowly, but steadily.
It took a rather embarrassing amount of time for Saitama to figure out his own feelings towards Genos. He quickly came to realise that the cyborg's presence alleviated some of the emptiness he felt, but he has assumed he had simply been lonely. It wasn't untrue, really. But with Genos he... felt. More than he had in years. It wasn't always good: worry, fear, anger, an unfamiliar protective urge that had confused him at first. Genos could take care of himself -he was S Class after all- he clearly didn't need Saitama babying him. Logic didn't seem to quell the feeling. But sometimes, during quiet moments at home, when Genos was cooking and Saitama was holding manga in front of his face and staring blankly at one panel, he'd notice that the empty feeling had gone. It always came back, because things like that didn't go away so easily, but being without it for a while was nice. Refreshing and comfortable in an unfamiliar -though not unpleasant- way. He's fairly certain it happens more often than he's aware. He doesn't usually notice because that's what it's supposed to be like. He's supposed to feel warm and happy when he's with the person he lo- likes. The person he likes.
It wasn't until sometime later that it really clicked. He and Genos were on their way home from the supermarket when it happened. It was getting late, the sun having fallen below the horizon, leaving the streetlamps to bathe City Z with their artificial light. There were stars out, Saitama remembers. He remembers looking up at them and smiling, light and happy. Space and astrology had interested him as a child, and he used to enjoy starting up at the night sky and just wondering. Since he'd begun training he'd forgotten his love of the stars. It was a shame, he thought. They were beautiful, in an everyday kind of way; somehow still breath-taking after all the hours spent starting at them as a child. So warm and bright and brilliant, but too far away ever to touch.
Genos is like that. The hero found himself thinking, cliché as it was. A star, in more ways than one. The cyborg himself walked quietly beside his teacher, oblivious to the older man's thoughts and to the constellations glittering above them. Saitama felt the need to share the sight, and the warmth it brought him.
"Oi, Genos," Saitama said, stopping his disciple with a gentle squeeze of his arm.
"Look." The hero grinned, tilting his head back to gaze into the sky again. There was something soothing about it. That despite his strength there were still things he couldn't have, things he still held in common with the rest of the world. The stars were too big and too bright and too far even for the strongest man on earth.
Saitama heard Genos hum in appreciation.
"They are beautiful tonight, sensei." He murmured. Saitama smiled. The streetlights bathed his friend in artificial amber light, mixing with the pale glow of the moon and stars to make something gentler. Genos looked soft, less far away than he'd seemed. Like something Saitama could reach. Could have, if Genos would have him in return.
Genos was starting at him, he noticed. Probably because he'd been staring first.
"What? Have I got something on my face?" Saitama asked, feeling the tips of his ears heat up. Genos briefly looked like a dear caught in headlights before composing himself.
"I can see the reflection of the stars on your head, sensei." He said seriously, thought he was clearly trying to hold back a laugh.
"You little brat!" Genos giggled at that, dodging the playful punch Saitama swung at him.
"My apologies, sensei!" Genos barked, grinning impishly. Saitama scowled, papping the cyborg on the forehead with his knuckles. The grin slipped off Genos's face at the gesture, replaced with an unreadable expression.
"Oi, Genos? You okay?" Saitama asked, squinting as he tried to decipher the look on his friend's face. Genos seemed to be... blushing? For a moment Saitama wondered how that was even possible, before he noticed that the normally yellow-orange lights on Genos's chest had turned a slightly alarming shade of red, casting his face in a pinkish hue.
"Ah, sensei, I seem to be overheating." Saitama could hear the soft whirring of what he assumed were cooling fans emanating from his friend's chest.
"Is something broken?" He asked quietly, poking Genos through his shirt.
"N-no sensei." Genos stammered, averting his eyes from Saitama's face. He's embarrassed! he realised, grinning. It couldn't hurt to tease Genos just a little bit.
"Are you sure?" Saitama asked, leaning closed and pressing the back of his hand to his friend's forehead.
"You're hot." He said, fighting back a smirk when Genos twitched at his choice of words.
"My cooling systems are, ah, struggling to cope with the output, s-sensei I-" Saitama cupped his cheeks, gently tilting his head to the side, pretending to check for damage. Genos's face felt surprisingly soft. And warm. The synthetic skin even felt real, if perhaps a little more solid that typical human skin. It had to be resilient, Saitama supposed.
"Genos..." Saitama felt like he should put the cyborg out of his misery. Genos was cute when he blushed, but he didn't want to go too far and upset him.
"Se- Saitama..." The hero's eyes snapped up the meet his friend's, wide with surprise. He saw Genos lick his lips, an unfamiliar movement. He'd never seen the cyborg do that before. It was unlikely he actually needs to since his lips couldn't get chapped, synthetic as they were. Saitama wondered if they were smooth and real like Genos's cheeks were, wondered if they were soft.
They were close. So close it only took a tilt of the head for Saitama to press his lips against Genos's. They were soft, slightly slick, pleasantly warm and smooth. Genos tried to kiss back, but he was a little too eager and not quite experienced enough. It wasn't a bad kiss, though. It was more intimate than they'd ever been before, but it felt natural and Saitama was not about to over-think it. He'd never felt anything more real than this.
[Sensei count: 10.5]