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Chapter Text

Since the beginning of time, the world has been fascinated by the number 'seven'. From naming the seven musical notes and seven colors of the rainbow to broader terms like the seven days of the week and seven continents of the world.  

Genos may be a cyborg, but he is still a human no less. He was no exception to this odd fascination either. However, rather than being interested in the wonders of the world, Genos found himself borderline obsessed with the seven contradictions of his sensei instead. 
 
And soon, he will reach the conclusion that Saitama is far more captivating than all the wonders in the world combined. Wonders in which Genos has no intention to share with the rest of the world. 

Contradiction 7: Oblivious but Wise

Gloomy fog clouded the sky, dark smoke lingered in the air, charred debris scattered on the ground. The cyborg hero looked at the remains of the fallen monsters around him and breathed a sigh of relief. They didn’t manage to save the city from destruction, but at the very least, they did save the people.

Genos glanced to his side, quietly admiring his sensei’s silhouette from afar.

The S-class hero couldn’t have possibly won this battle against the dozens of Demon-class monsters, not without the help of his sensei. His sensei, ever the man with perfect timing, had come at the right time when Genos was almost out of artillery.

And just like that, Saitama saved the day once more, with his signature one punch to end it all.

Genos wondered to himself, as he watched a ray of sunlight sip past the dark clouds only to shine sublimely on his sensei’s white cloak. How did sensei’s cloak manage to stay clean after such a gory fight?

Mentally noting to follow up on this observation later, Genos began to limp towards his sensei with his one good leg, while holding the other detached metal limb in his hand.

“Sens-“, Genos started to call out, only to watch his sensei turning in the other direction.

Huh?

Genos squinted towards the direction his sensei was jogging in, confused as to what he was doing. Turning on his heat detector in his vision to identify the issue, Genos gasped soundlessly as he recognized the humanoid figure behind the rubble.

Half-expecting to see a barely alive monster lying on the ground where sensei was going to exterminate, Genos couldn’t believe his eyes that there was still a human in the vicinity.

What? How is this possible? Authorities blared the sirens hours ago, evacuating any humans in the city.

So why was there still one person hiding right in the middle of the battleground?

Genos limped to his sensei’s side as fast as he could and stopped short a step behind him. There was a citizen; a young man, more of a teenager really, crouching in fear behind some large boulder. As expected, he was trembling in shock with tears flowing freely down his face. His hoodie and jeans were dirty with soot but otherwise, he seemed uninjured.

The cyborg raised his voice then, not bothering to hide his frustration, “Why are you still here?! Didn’t they raise the Martial law hours ago? Do you have any idea how dangerous it is to stay here? Are you stupi-“

Saitama raised a hand then, signaling him to stop.

Genos closed his mouth immediately, solely because his sensei instructed him to. But that was also when Genos realized, that it was odd, that the kid had never once looked up to them despite Genos’s loud beratement.

He had never once shown any signs of acknowledgment of them. His arms hugged his knees tightly, and his head was tucked down.

Genos watched as his sensei approached forward, slowly squatting down in front of the civilian.

Saitama gently tapped on the kid’s knee, at which he instantly looked up to see them. His eyes widened as if he had just noticed their presence.

The bald hero removed his gloves and dropped them on the ground beside him. Tilting his head to a side, Saitama pointed a finger to the kid, then proceeded to make a thumbs-up gesture; which Genos instantly understood as sign language, asking if he was okay. 

 “… He’s deaf.”, Genos whispered to himself, realizing his blunder.

The teenager's eyes lit up the second Saitama did the hand motions and a look of relief swept across his face. The intensity of hope in his expression; was as if Saitama was a guardian angel sent down to help him. In that instant, Genos understood his feelings very well, for Genos had been in this position, more times than he would like to admit.

For every single time when Genos was in danger and Saitama had come to save him, he had felt the same way; but in manifold degrees more.

Do I always have this expression on too? , Genos thought. Then, it was no wonder why it was so painfully obvious to his fellow S-Class heroes that Genos was utterly infatuated with his sensei.

Genos didn’t think it was possible but the teenager cried even harder than before, while vigorously nodding his head to Saitama's question.

Saitama gave him a reassuring smile, the kind of smile Genos rarely got to witness and a small part of him felt uneasy that Saitama was giving it so easily to a stranger. 

His sensei continued, pointing at the kid once more, then brought two of his index fingers together and twisted them slightly, which Genos interpreted as, "Are you injured?"

The kid shook his head, indicating that he was fine, seemingly to have calmed down a little.

Saitama inched forward to wipe away the kid's tears with his sleeves and that was when Genos's uneasiness grew. The kid stared at his sensei with a newfound sense of fondness and Genos didn’t like that.

No, he didn’t like it one bit .

His sensei signed once more, bringing his hands together to form a cross, and then moved them apart slowly; meaning to say, "You are safe now."

At this point, the kid rushed forward to hug his sensei, and his hoodie fell back in the process to reveal his hearing aid. In turn, Saitama fell back a little following the momentum of the hug. But Genos was having none of that for a second longer.

Guided by his instinct of not allowing anyone to touch his sensei, the cyborg easily pulled the teenager away by his hoodie, quickly detaching him from his sensei.

It was only then that Genos realized what he had done. Hurry to rationalize his action, Genos explained, "I should bring him to the nearest medic, just to be sure that he's alright, sensei."

Saitama, as oblivious as ever, nodded to his excuse, "O-Oh yeah, you should do that."

The kid then looked at Genos, the look of admiration now onto him and it was Genos's turn to be hugged.

Reluctantly, Genos patted on the kid’s shoulder. Genos didn’t care for it as long as the kid wasn’t holding onto his sensei.

The kid signed to him rather enthusiastically, “I am your fan, Demon Cyborg! Thank you for saving me! You're my hero!”

Genos nodded, although he internally scoffed at the superficiality of the so-called fan. This kid didn’t deserve to be his sensei's fan after all.

Peeking to see his sensei’s reaction, Genos was surprised to see that his sensei was already standing up to dust away the dirt on his hero’s outfit, blissfully unaware of their interaction.

Genos grimaced when he noticed the pristine white cloak had turned black with soot now. He shouldn’t have touched sensei, look how he had sullied him.

Just then, the Heroes’ Association reinforcement arrived, along with paramedics ready to assist the civilians. The teenager was swiftly escorted away, leaving Genos with his sensei alone once more.

Genos limped towards his sensei, eager to be the sole receiver of his attention this time. Saitama looked at him up and down, frowning, “Genos, you’re hurt again.”

The cyborg tried to look sorry, for worrying his sensei. While it was true that Genos felt bad, the similarly small part of himself felt gleeful that his sensei was caring for him, thinking about him, looking at him.

Genos decided that something must be wrong with himself but that error could be fixed later, it shouldn’t be something he should think about when his sensei was right in front of him now.

“Do you need to go to Dr. Kuseno for this?”, Saitama asked as he inspected the torn limb Genos was holding.

Genos smiled at his sensei, “There is no need for that, I can easily fix this myself, sensei.”

“Are you sure?”, Saitama questioned, looking visibly upset.

Genos nodded, “There is no need to worry, sensei. I don’t feel pain like normal humans do.”

“But still…”

“We should head home now, sensei. The association will be doing housekeeping soon.”

Saitama hummed in agreement and began walking at a much slower pace to accommodate Genos.

Without delay, Genos began to ask his burning questions; “Sensei, when did you learn sign language? How did you know the kid is deaf? How did you know he was even there?”

“I see you’re still very energetic, huh?”, Saitama teased, though Genos noticed his sensei glancing at the limb, still clearly concerned for his wellbeing.

“Please impart your wisdom, sensei.”

Saitama shrugged, “Dude, it’s not a big deal, it’s just basic sign language.”

“Where did you learn it, sensei?”

The bald hero scratched his cheek, looking a little awkward, “… Erm, from anime?”

“As expected of sensei.”

“Are you making fun of me?”, Saitama retorted, his ears visibly turning pink.

“Quite the opposite, sensei.”, Genos beamed, noting his sensei’s shyness. “What about the kid? His hearing aid was hidden by his hoodie, how could you tell then?”

“It is clear, isn’t it?”, Saitama said matter-of-factly. “He wasn’t covering his ears the whole time.”

Genos paused in his steps, a bulb lighted up in his head. That is true, he didn’t cover his ears despite the gruesome slaughtering of monsters on the ground.

Right then, Saitama stopped walking as well and turned on his heels immediately, “Oh no! I forgot my gloves!”

He glanced at Genos, “Just give me a minute, I will be right back!”

The cyborg smiled to himself, as he watched his sensei sprinting away. It was silly to watch, that Saitama can be wise yet so adorably clumsy, that he can be so attentive to others yet so careless about himself.  

But to Genos, it simply did not matter. Because to Genos, all of it, is just simply, endearing.   

Chapter Text

Contradiction 6: Quiet but Profound

It began about a week into living with his sensei when Genos started to notice the gentle humming from him.

Maybe it was a regular habit of his sensei's or maybe sensei was subconsciously doing it, Genos couldn't be sure. Saitama didn’t do it often either, perhaps when he was just idling around reading his mangas or when he was preparing food in the kitchen.  

It was just… soothing to Genos’s ears. A peaceful voice belonging to a quiet person in the tranquil apartment that they shared. Genos did not remember when was the last time he got to experience such serene peace. Saitama didn't just give Genos a new life, he gave him hope; hope in which he can have joy like a normal person. That was so much more than Genos could ask for after a long day of fighting monsters and plotting revenge against the Evil Cyborg. 

Genos didn’t think much of it in the beginning, simplifying it as one of the little quirks of his sensei.  

That was until when he witnessed Saitama singing on the balcony one late evening as he returned from the association’s weekly meeting. 

Genos first heard the beautiful melody outside the apartment door. It was muffled, but Genos recognized Saitama’s voice right away. Fearing that his sudden entrance would interrupt Saitama, Genos opened the door as quietly as he could. 

Saitama was squatting on the balcony’s floor, watering his cactus plant with his elephant watering can as usual. His back was to Genos, completely unaware of his disciple’s presence. The cyborg didn’t take any chances as he immediately started to record the scene in his optics. He was utterly and completely bewitched. 

Genos never had a shortage of words, but at that precise moment, he had no words to describe what he was seeing, hearing, and feeling. A transparent veil slowly formed around the tiny apartment, separating them from the external world. An asteroid could hit the ground outside, a God-level attack could be at their door, but Genos wouldn't even have noticed. 

Is this what it feels like to be entranced? To be seduced by a siren? To be hypnotized?  

The cyborg smiled to himself, grateful that he had the chance to even share the same space with his sensei. Quietly and effortlessly stealing away my heart, only you can do that, sensei. 

Genos listened serenely as his sensei sang the last line of the song. 

Saitama stood up from his spot and turned around, only to drop his watering can as soon as he saw Genos standing in the hallway. Instantaneously, the perfect bubble that Genos imagined around them popped.

“How long have you…”, Saitama trailed softly before trying again, “How long have you been standing there?” 

Sensing the discomfort in Saitama’s voice, a completely different tone from seconds before, Genos instantly apologized, “I’m sorry, sensei, I didn’t mean to intrude. I was just back from the meeting an-“ 

“No, I’m not... it's just...”, Saitama interrupted his apology, "… Nevermind." 

Did Genos do something to offend his sensei?  

Saitama picked up the can and placed it back at its usual place, before hurriedly walking past Genos in the hallway towards the door.  

But Genos didn’t let him go, instead holding onto his arm in the narrow place. His eyes searched for any sign of distress in his sensei's expression, but his sensei was clearly avoiding eye contact. 

"Did I do something wrong, sensei?", Genos asked guiltily.  

"What? No," Saitama sighed. He hesitated for a moment, "I just need to... I need to go for patrolling real quick." 

"In your pajamas?", Genos stared skeptically at Saitama's blue-striped jammies. 

His sensei easily released himself from his grip, "Y-Yeah, just a quick one." 

"There is nothing wrong with listening to sensei singing, is there?", Genos questioned desperately, wondering if he offended his sensei in some sort of intrusive way. "I mean, sensei hums all the time in the house anyway."

The moment Genos said that, the air in their cozy little apartment went still. Never in his mental calculations did Genos anticipate Saitama's reaction; the look of complete shock colored his expression, which in turn surprised Genos.

But there was something else too, something behind his sensei's widened eyes, is that fear?

"... I do that all the time?", his sensei's voice was unbelievably soft, almost as if he was asking himself more than to Genos.

Genos swallowed hard, unsure what to reply to ease his sensei's apparent anxiety. Opting to just be honest, Genos could only nod, "There is nothing so terrible about it, right?"

Saitama shook his head, though that did not seem to be answering Genos, instead more as if it was a reflex to his internal thoughts.

His sensei reached for the doorknob, but before he left, he gestured towards the kitchen, "I prepared dinner, you should heat it up and finish it."  

And then, just like that, his sensei was gone; as if Genos had been abandoned.  

Genos had the idea to chase after his sensei, to ask him what  exactly  was wrong, but he had an inkling that Saitama wanted to be left alone.  

Heading into the kitchen, Genos stared half-heartedly at the plastic-wrapped dishes on the counter, that Saitama had cooked for him. Yet, Genos had lost all his appetite.  It didn’t matter even if the dishes were the best delicacies in the world. If Saitama wasn’t there to have it with him, Genos rather not have any at all.  

Appetite, however, would not be the only thing that Genos lost that night. Little did Genos know, he had also lost the privilege of ever hearing Saitama's humming from that day onwards.

Chapter Text

Contradiction 5: Nonchalant But Altruistic  

Ever since the incident where his sensei went patrolling in his pajamas, Genos had never heard the sweet, soft melody coming from Saitama again. Not even the quiet humming anymore.  

Saitama had returned later that night, pretending everything was normal. Meanwhile, Genos, who was cautious of affecting his sensei in any way, didn’t dare to question it further.  

But just because Genos didn’t dare to ask about it, didn’t mean he wasn’t curious. For now, though, Genos wouldn’t rush things off. He figured that Saitama was probably not used to another presence in his home yet. And perhaps, it was time to pay his sensei back instead. He who had taken strange comfort in his voice should return favors to his sensei now.  

So, Genos started with the small things.  

It began with a few snacks and sweets, some desserts here and there. Genos paid attention, when a new brand of potato chips caught his sensei's eyes. Genos took note, when Saitama took out his small purse and calculated the coins he had, and decided that he didn’t have enough to afford the snack. Genos watched, when Saitama placed the bag of chips back on the rack.  

And then, he would proceed to buy it right after.  

Saitama had been reluctant at first, "You don’t have to buy it for me. It's not on sale anyway." 

But Genos would have learned his sensei's pattern by now, swiftly maneuvering the conversation in his favor, "I wanted to try it too, sensei. It's a viral brand these days."  

Saitama looked half-convinced, and Genos prompted more, "I was worried I wouldn’t like the taste, if it's not spicy enough. Can sensei try it for me?" 

When Genos put it this way, Saitama would  think  that he was helping Genos instead of feeling indebted, hence could freely enjoy the snacks that came his way.  

This method would be utilised by Genos continuously with slight deviation every time, and over time, Saitama would stop questioning it altogether. 

Saitama has always been a man of few words, which made Genos all the more eager to cling to his every word and to thoroughly analyse his body language to the finest details. From his sensei's strangest ability of wiggling his ears to his preference for udon over ramen, Genos would carefully catalogue them in his core memory system. Some might see it as a terrifyingly intense obsession, but Genos begged to differ. It may be fanatical and all-encompassing on the inside, but on the outside, it was just a quiet devotion.  

There were temptations, all the time, when Genos had wanted to shout out his feelings, when Genos would have the urge to rush forward to hold his sensei. But Genos pushed those feverish thoughts away.  

Because none of his emotions matter, only Saitama's do.  

Genos was a young boy who had lost everything, and now, he had found an anchor, a rock, a God. A powerful, sometimes clueless, but selflessly kind God. Saitama had shattered all his cynical expectations, shifted his entire world view, and given him a meaning to life. There was more to living than just revenge, that there is so much goodness in the world, that there are things still worth protecting.  

A simpleton like his sensei had given him hope, a future after his mission of annihilating the Mad Cyborg, a permission to stay by his side after all of that is over.  

If Genos were to follow his selfish desires and do something to Saitama without his consent, Genos wouldn’t be able to live with himself. The young cyborg is never afraid of death or pain, but the one thing he fears is losing Saitama. To do anything which may make Saitama uncomfortable was unthinkable. If Saitama doesn’t accept him, Genos would quite literally shatter.  Genos would do all he could so that he could stay by his sensei's side. 

And so, Genos waits. Loyally, patiently, willingly.  

"Genos?" Saitama called out from the bathroom.  

"Yes, sensei?" came Genos's instant reply from the kitchen as he was preparing dinner. The cabbages were left half-sliced on the cutting board as he quickly attended to Saitama's request, whatever it may be.  

His sensei opened the door partly, his head peeked out a little to see Genos already standing at the doorway, at attention.  

Genos could see Saitama's bare shoulder partially hidden behind the door, and he resisted the impulse to peek further down his sensei's body. The cyborg may undeniably be a pervert for his sensei (and only his sensei), but he still had the last thread of self-control in him. He'd rather blind himself than make his sensei self-conscious about it.  

"This," Saitama held out an arm. In his hand was a yellow bath bomb, in the shape of a duck. "You bought this, didn't you?"  

Genos nodded. He had seen his sensei looking through the glass window of a retail store displaying various cute merchandise featuring yellow ducklings, when they were out grocery shopping. He had seen Saitama smiling softly at the cutesy designs, momentarily absorbed by the pastel-colored trinkets.  

The cyborg found it ironic that the strongest man in the world would like adorable things like these. It wasn’t exactly a surprise, however, as Genos has seen the fair share of things that Saitama owns. Sensei's giraffe keychain hooked to his house keys, his green elephant watering can, his green kiss lock purse, the yellow plastic duck on his bathtub, the pink frilly apron he owned that Genos now used instead.  

There was no other way to describe his sensei's quirks, other than saying that it was all downright  lovable .  

"Why would you buy this silly junk?" Saitama chided, but his tone lacked anger. If Genos had to guess, his sensei sounded elated even. "It must have been expensive too!" 

"But sensei likes yellow ducky," Genos's core brightened a fraction as he caught a small smile slowly forming on his sensei's face.  

"Well, I do like it, but-" 

"Then, that's enough of a reason." 

Saitama cleared his throat, but Genos already saw through his mask of nonchalance. His sensei was clearly excited about something as mundane as a bath bomb. If a small piece of soap can make his sensei twinkle, Genos would never even hesitate to buy him the entire line of retail stores.  

"D-Don't waste money on buying useless things like this again, okay?" Saitama scolded without spite, "I taught you well enough about frugality." 

"Sure, sensei," Genos concurred, despite knowing this wouldn’t be the last time he would spoil his sensei.  It's not useless, if it can make you smile.   

It had been a long day for Genos; from attending the Heroes' Association meeting in the morning to fighting off monsters at City B till late evening. It had been a gruesome fight, but Genos was miraculously left undamaged, safe for a few scratches here and there.  

Sensei will be proud , Genos thought to himself, as he made his way home hurriedly. Saitama had sent him a text, to ask him to be back by dinner time, and Genos was never one to defy his sensei.  

By the time the young disciple returned to City Z, the sky was already dark. As Genos looked up at the residential building to see a yellow light flowing out of their apartment, indicating that Saitama was home, a sense of warmth flowed through his body, and his mental fatigue gradually healed.  

Walking up the stairs to their home, Genos could smell a delicious aroma sipping out. Eager to know what his sensei was cooking, Genos excitedly opened the door to greet his sensei, "Sensei, I'm home!"  

"Oh, Genos, welcome home," Saitama replied, his head poked out of the kitchen to greet him quickly. "I made dinner, let's eat together." 

Genos enthusiastically nodded, "I will set up the table right away, sensei!" 

As Saitama brought out the dishes, and placed them in the centre of the table, Genos noticed it immediately, "How did you know?" 

His sensei froze momentarily before quickly making his way back to the kitchen to get the bowls of rice, evidently avoiding eye contact, "Erm, the doctor of yours, he said you like sardine in oil, the spicy kind." 

Saitama continued to place the cutlery, his actions somehow a little awkward, "I- I was craving spicy food too, so..." 

"You cooked it for me, didn't you?" Genos whispered, but loud enough for his sensei to hear.  

"… You are treating me a lot these days. The snacks, the bath bombs and all," the bald hero looked away, scratching his cheeks absentmindedly, "You even bought me a whole tray of drinks just because I was looking at the vending machine the other day." 

Sensei noticed,  Genos thought,  My efforts, none of them are in vain.   

"I wanted to do something for you in return," Saitama continued ineptly, "But I won't guarantee if it's spicy enough for your taste, okay?" 

Genos could only nod to his sensei's kindness, for he couldn’t trust what sort of confession would come out if he had opened his mouth.  You could feed me a bowl of sand, and I will still be grateful, sensei.   

The bald hero began scooping large pieces of sardine, piling them on Genos's bowl, "I know you said that you don’t feel pain like humans do, but you should still enjoy good food like normal people do."  

Genos could only stare at his sensei, astonished that Saitama remembered the things he said. His sensei, who had reprimanded him multiple times to keep his sentences under twenty words, his sensei, who was so indifferent about many things, had paid attention to  him.   

Saitama began to frown uncertainly, as if second-guessing himself, "Why are you not eating? Is my cooking bad?" 

Instantly, Genos shook his head vigorously, "I will eat now, sensei! I will finish it all and lick the bowl clean!" 

"You don’t have to go that far," Saitama beamed slightly, "There's more in the pot if you need." 

His sensei began to eat as well, only to cough harshly a moment later, "This really is a bit too spicy." 

Genos rushed to the kitchen to retrieve a glass of water and hurriedly returned to his sensei's side, "I'm sorry, sensei. It's my fault." 

But Saitama only chuckled, "Idiot, how is this your fault?", and proceeded to drink a sip of water. "I was the one who cooked it." 

The bald hero ruffled his hair gently, and Genos looked up to see the light twinkle in his eyes, "I mean, I know you're like 99% metal, but you are still just a kid to me. Be a little selfish sometimes, okay?"  

Genos didn’t think he could possibly love his sensei more, but once again, Saitama proved him wrong. In the eyes of the Heroes' Association, Genos is a weapon of mass destruction, a monster-killing machine. In the eyes of his fans and civilians, Genos is a handsome face on a metallic fuckboy body.  

But to Saitama, Genos is human. Just a person deserving of needs and wants.  

"… You want me to be selfish, sensei?", Genos asked quietly. He thought of all the things he had dreamed of doing to his sensei. Oh, how he had desperately wanted to hold his hand, to caress his face, to kiss him, to touch the most sensitive parts in his sensei's body.  

"Yeah, Genos. Act a bit your age," Saitama encouraged him.  

Sensei, you have no idea what you're wishing for. If only you knew what I wanted to do to you, would you be so openly accepting? Would you... accept me?   

"I...", Genos inched forward, his hand slowly reaching out towards the apple of his eye.  

But at the very last second, Genos retreated. He held back. Because deep down, Genos knew, now was still not the time.  

His sensei was too precious to him for him to do something so careless; he didn’t want to creep Saitama out.  

"… I want to hear sensei sing again." 

"Eh?" Saitama was thrown off by his request. 

"Why did you stop doing it, sensei? Did I make you angry?" Genos asked pleadingly as he watched Saitama back away a little.  

"No, you didn't ma-", Saitama answered but hesitated, "It's the other way around actually." 

"Huh?" Genos asked, genuinely confused.  

"… I just thought, it might annoy you. I lived alone for a very long time now, I know I have some weird habits that you may not-" Saitama paused, "I don’t want you to-" 

"I won't move out, if that is what you're worried about, sensei," Genos cut in, his tone serious and final, leaving no room for doubt. "Even if the sun falls on  our  apartment, I am staying in place."  Right next to you.   

Saitama looked him in the eyes then, and Genos stared resolutely back, insistent to remove any of his sensei's wariness. A moment later, his sensei abruptly looked away and began stuffing his mouth with rice.  

"You don’t have to be so corny," his sensei mumbled with his mouth full, "Eat your food before it gets cold."  

Saitama was pretending to be casual, but Genos already saw through him anyway, "So... will you sing for me, sensei?" 

Saitama's gaze was on the television, but Genos  knew  his sensei wasn't registering anything on the screen.  

His ears were slowly but surely turning red, but Saitama did reply, "… If I feel like it."  

Genos smirked and nodded as they resumed eating in peaceful silence, with the television playing softly in the background.  

The cyborg still did not manage to hear his sensei's melodious voice that night, but that was fine. Saitama had told him to be selfish, yes, but he didn’t tell his disciple to be greedy.  

And so, Genos waits again. Exhilaratingly, blissfully, and as always, willingly.