It has been so long since I've written anything...so if this sucks that's why! I fear that Saitama may be a little OOC in this...but I really love the idea of Genos being a little eager slut for his sensei!
"Mmm~ sensei...Saitama-sensei~"
Coming to halt with his hand hovering over his doorknob, Saitama's expression went concerned, hearing what sounded like moaning coming from inside his apartment. He had just got back from a solo trip to the grocery store, which was a rarity nowadays now that Genos had began living with him. Usually the blonde cyborg would have jumped at the opportunity to go anywhere with his sensei, but when Saitama had told him he was heading out Genos just replied with "Call if you need anything!"
Furrowing his eyebrows, Saitama placed his ear against the door, his hand silently sliding forward to grip the doorknob.
"Yes...mmm, yes it smells just like sensei...so good!"
Gripping his plastic grocery bag tight in his fist Saitama threw his door open, nearly busting it off it's hinges as he charged into the living room, unsure of what he was about to witness. Saitama stopped in his tracks, staring down at his roommate with a dumbfounded expression on his simple face. "G-Genos?"
Black and gold eyes darted up towards Saitama in surprise, the sound of Genos gasping something that the bald hero had never heard before. "S-Sensei!" The cyborg was kneeling on the floor, their laundry basket tipped over with the unwashed clothes spilled across the small table they usually shared meals at. Genos had Saitama's favorite yellow hoodie gripped tight in his metal hands, his face pressed against the words OPPAI where he had his nose shoved moments ago. A hot, rose colored blush crept across Genos' face as he was frozen in shock, looking up at his roommate's uneasy and unsure face.
"Were you sniffing my clothes?" Saitama asked with a straight face, already knowing the answer.
Genos was visibly shaken, small beads of sweat covering his face, his body quivering as he still gripped the hoodie to his chest, and oh wait- he was turned on! Saitama gulped down a lump in his throat, suddenly realizing the level of the situation. "Genos...were you getting off on my dirty laundry?"
The red blush was now consuming Genos' entire face as he was finally able to turn away, hugging the clothing even closer to his body. "I'm so sorry sensei...I just admire you so much and at some point I suppose it turned into something more..." Genos was ashamed that his teacher, the one person who he essentially saw as God tier had caught him in such a perverted act.
As Genos had turned away, Saitama looked further down, noticing that the blonde had no pants on. Feeling his own face heat up a little, Saitama peered on, finding out that Genos...had no genitals. The bald hero had never thought about it before, but his roommate's body was basically 95% robot, so it did make sense that Genos didn't have a penis. Saitama began feeling a little adventurous, the whole situation sparking his interests a little more than he would have liked as he felt himself grow a little beneath his sweatpants. He suddenly wondered if his cyborg roommate could even get off.
"Genos...I'm going to have to punish you, you know this right?"
Genos whipped around, tossing the yellow hoodie to the side as he assumed the position, bowing forward with his hands balled on top of his knees and his forehead pressed against the floor. "Yes sensei! I'll do anything to earn your forgiveness!" Saitama felt his pulse thump quickly as he dropped the grocery bag onto the table, stepping up to Genos and stopping right in front of him.
"Sit up," Saitama said calmly, watching as Genos began obey. As the blonde lifted himself back up, he froze once more, his face inches from the front of Saitama's sweat pants. He hadn't realized his teacher had come so close to him. "S-sensei?"
"You said you would do anything right?" The bald man repeated Genos' previous words, those black and gold eyes slowly moving up to stare at his master. The cyborg nodded with a confused yet eager expression, his cheeks once again hot and red. His body began to tremble, Saitama's scent being so much stronger now that he was right next to the real thing. Saitama smirked a bit, bringing one hand forward to slide though Genos' spiked blonde hair, the other now tugging down at the waistband of his black sweatpants.
"Please your sensei until I say that you can stop," Saitama attempted to sound commanding, pushing his pants down far enough for his half hard length to slide out, Genos' eyes going wide as he stared. Saitama's hand had halted at the top of his roommate's head, his fingers gripping lightly at his hair. "Do I make myself clear?"
"Y-yes sensei~" Genos swallowed dryly, the core in his chest whirring at an alarming pace. He now knew at this point that Saitama had no real intentions of punishing him for his perverted actions...but this was the last thing the cyborg would have expected. With a shaky breath, Genos leaned forward, pressing his lips to the tip of his teacher's cock.
"Lick me until I'm hard..." Saitama bit against his bottom lip, watching as Genos' lips parted at his command, his wet and pink tongue coming out to slide against his aching flesh. The older man groaned softly, feeling the warm saliva begin to drip down his length, Genos' languidly lapping it up before it could drop. A small, quiet moan came from Genos' throat, the taste of Saitama overwhelming his circuits as he dragged his tongue up the underside of his sensei's now fully erect dick.
"G-good Genos..." Saitama started breathlessly, bringing his free hand forward to grip at Genos' jaw. "...now open up, nice and wide."
The blonde complied immediately, slowly parting his wet lips and opening up his mouth, waiting anxiously for his sensei. Saitama's pulse raced as he looked upon his extremely erotic sight, Genos' expression holding immense pleasure as his hot breath ghosted over his throbbing cock. "Please use my mouth until your needs are fulfilled, sensei~" Genos smiled slightly, attempting to keep his mouth open wide. The bald hero almost moaned as he heard this, his hips automatically moving forward.
"Mmphmmm~!" Genos moaned deeply around Saitama's cock as he slid it inside the blonde's eager mouth, feeling his wet lips circle around him. Saitama hunched over slightly, his breathing shaky as he stared down at Genos, the heated lust enveloping his face too much to handle. Genos was all too willing and happy to suck him off. A thought briefly passed through the hero for fun's mind. "Has Genos fantasized about this before?"
Holding Genos' head steady by the firm grip at his hair, Saitama began to pull out, only to thrust back into his roommate's mouth slowly. Another high pitched moan resounded in Genos' throat, his eyes rolling back as his tongue quivered against the underside of Saitama's thick length. "Please sensei...please fuck my mouth!" , is the only thought that was coursing through Genos' mind.
"Sh-Shenshei..." Genos attempted to coax Saitama to go faster, his black eyes wet with oil as he stared up at his sensei. Saitama felt his abdomen clench at the vibrations going through his dick when Genos tried to speak.
"Oi-" Saitama clutched at Genos' chin a little tighter, tugging at his hair a little rougher. "...don't talk with your mouth full."
Just as Genos was about to apologize he was cut off by Saitama suddenly pulling back and slamming into his mouth. A wave of pleasure rippled through both of them, the gooey wetness of Genos' compliant mouth warming Saitama's whole body. The bald hero began to go at a steady pace, his cock pressing roughly at the back of Genos' throat with every thrust, the teenager's quivering lips struggling to stay wrapped around his master's length as he felt the urge to cough, but held it down. Saitama groaned quietly, staring down as his cock slid in and out of his roommate's swollen and slick lips, saliva beginning to drip down the younger man's chin with every pounding motion. Genos' cold hands were gripping at Saitama's muscular thighs, the sensation of his mouth being fucked sending him over the edge.
Genos' let out a struggled cry, the under wiring of his arms and legs glowing a hot golden color as he squeezed his eyes shut, orgasm taking over his overheating body. "Mmphm! Shenshei~mmph!" The blonde moaned and cried, the vibrations from his mechanical body reverberating onto Saitama's cock. The bald hero groaned loudly, his hands coming to rest gently on the sides of Genos' head. "Prease senshei...don't stohp..." Genos grinned around Saitama's thick length, suddenly beginning to move his head on his own, leaning forward to suck at Saitama's cock with earnest.
"Ahh- Genos!" Saitama knitted his eyebrows, breathing raggedly as he watched Genos bob his head back and forth, sliding his dripping cock out of his mouth to rest it against his cheek, his tongue licking stripes up its side.
"You taste so good sensei~ please let me pleasure you more!" The cyborg groaned against Saitama's cock, his saliva covered lips smiling as he began swirling circles around the tip with his sticky tongue, taking it into his mouth and sucking gently at it.
"G-Genos..." Saitama finally closed his eyes, the sensation proving too much as he felt his peak hit, his thick cum squirting into Genos' warm mouth. The blonde made a pleasured noise as his mouth was filled, continuing to suck Saitama dry, swallowing all of his master's release.
"Y-you can stop now..." Saitama chuckled breathlessly, watching Genos' swollen lips finally release his softening length.
"Was it good sensei? Do you forgive me for what happened earlier?" Genos asked, his eyes big and happy as he stared up at the exasperated Saitama. The bald hero smirked, pulling his pants back up as he reached down and grabbed his yellow hoodie, chucking it right into Genos' face.
"No you pervert! Now go do the laundry!"