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It's Always the Quiet Ones

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Kai’s eyebrow furrowed as he graded his star pupil’s midterm; appalled at how abysmal his score was. Shaking his head, he didn’t understand why such a brilliant student had failed so spectacularly. 

He rubbed his temple, sighing, as he reluctantly wrote the letter “D” at the top of his exam. He needed to get to the bottom of this. 

Friday was when he returned the exams to his students. A great way to send them into the weekend right? Allows them to wallow in their failing scores or motivate them to get right back to work over the weekend.  Kai walked up and down the steps of the lecture hall, handing each student their exam paper. 

When his eyes landed on his favorite student, it was probably inappropriate to think so, but Izuku Midoriya was more than just his top student. He was just too adorable for words. His wide doe-eyes that shone effervescently, the faint blush that colored the skin below the dusting of freckles on his face. 

But today, Izuku was a nervous mess, fidgeting with his fingers, biting his lower lip, on the verge of crying. Kai handed his exam, “Please come to my office hours. This is very unlike you.” 

He heard a small whimper, as his student shakily exhaled dejectedly, “Yes, sensei.” 

Office hours were typically held for an hour from five o’clock to six. Not many students really came by on a Friday afternoon, so he’d hoped he hadn’t imposed too much on the young man’s schedule. The sun was beating down through the glass, his office feeling like a furnace even with the window opened all the way. He had undone the top buttons of his shirt, and rolled up his sleeves. No reason to be formal anymore, it’s after hours after all. 

A soft knock on the door was heard as Kai sat at his desk, looking over the top of his glasses when he said “Come in.” 

In walked the cute young man with wild green hair, he looked up, eyes widening before they were cast to the ground, unable to meet Kai’s gaze. He smirked at how shy his student was.

“Have a seat Izuku,” he said as he got up from his seat, to perch on the front of his desk to talk to Izuku more informally. 

Izuku stood as still as a statue before he stepped in, laughing nervously, “Umm, wow, is it warm in here or is it just me?”

“It is, but not much I can do about that. Please make yourself comfortable, and close the door,” as he saw Izuku forget to shut it as he made his way in.

He watched Izuku curiously as the young man hesitated, looking at him and at the door, “Um, are you sure?” 

“Of course, you don’t want anyone to eavesdrop on our conversation do you?”

He quickly closed the door, and headed to the chair in front of Kai, perching at the edge of the seat. He clutched his bag to his chest as he pulled out the poorly marked exam. 

“Se-sensei. I’m—”

“Izuku,” he said cooly, “relax. Don’t be so nervous. I called you in here because I was highly concerned by your performance. You are my top student, after all.”

“I’m really sorry sensei! It was,” his eyes flicked down at his chest and back up, “It was just an off day.” 

Kai slid off the desk, crouching low to be at Izuku’s eye level resting a comforting hand on his knee, “If you’re struggling with anything, you can tell me. I’m here to help you, I get how hectic student life is, but I just want to understand.” 

Izuku’s lower lip wobbled and he looked like he was having a panic attack as he met Kai’s eyes. Kai braced himself for a plethora of tears and a tirade of how stressful life was. 

His student looked like he was combust with how red he was turning, and then it happened. 

“Ithoughtaboutyounaked,” he said so fast Kai didn’t catch a word.

“I’m sorry?”

“I’m sorry but your tattoo was on display for everyone to see. I didn’t even know you had one. Who would’ve thought you’d have a tattoo and oh my god, how was it even fair with what you were wearing that day? You looked so freaking hot! I was so distracted with that and the heat, and then thinking about licking your tattoo and I just couldn’t,” Izuku’s eyes widened comically as he realized what he was spouting verbally. 

Jumping up to his feet he looked at a dumbfounded Kai who still hadn’t registered much of what Izuku had just mumbled. He watched as Izuku backed away, bowing quickly and saying, “I gotta—I gotta go, bye!” 

Kai sat there in his burning hot office, wiping the sweat from his brow, trying to decipher what just transpired. From his mumbling he picked up: tattoo, distraction, licking and hot. 

And he just scratched his head, “What on earth?” 

He closed up his office, and made it home for the evening. 

But the whole interaction still bothered him. What in the world had Izuku been muttering a mile a minute? It irked him to the point that he decided to call the young man and clear the air. He just couldn’t wrap his head around it. 

Pulling out the class roster, he rifled through all the contact info till he found Izuku’s number. He checked the time, it wasn’t that late to call him. Dialing the number he waited, the phone clicked, and the line connected. 

A giggle was heard on the other hand and a groan, “Stappp, Kacchan.” 


“Hmm?” He said sleepily, a brief moment of silence transpired and Kai could feel himself get irritated, “Oh, it’s you. Chisaki-sensei .” 

Kai jolted at the sultry sound that dripped from Izuku’s voice as his name rolled off his tongue. Deep, rich, smooth as velvet, it sent shivers up his spine.

“Izuku, about this afternoon.”  

“Yes, Chisaki-sensei . What can I do for you….or to you?

“...what?” Suddenly Kai felt heat under his collar at how Izuku’s voice was dripping in sex, Kai felt himself twitch in interest, till he heard screaming in the background.

“Oi, hang up your damn phone! You’re in no state to be talking to anyone!”

“Shut up Kacchan!”


“Oo,” Izuku cooed, “I like how my name just rolls off your tongue, Daddy .” 

Kai’s heart rate skyrocketed, “Izuku, maybe I should call—”

Kai heard a yelp and a scuffle, “Look, whoever this is. Izuku’s drunk off his ass, and KNOWS BETTER THAN TO ANSWER HIS PHONE .” 

Kai held the phone away from his ear as the person yelled at Izuku.

Deku. Learn to control your alcohol would ya? I hate having to look after your ass.”

Kai frowned when he heard a displeased whine in the back followed by muffled talking, why was Izuku already that drunk?

You damned brat!”

“Kacchan, give me my phone!” 

“Hey, sorry man. Roommate duty calls. Sorry, you had to witness that.” 

“Ah, that’s...fine? I’ll talk to him Monday then.” 

“Cool, later.” 

And just like that, the line went dead. 


Mmm, yes sensei—just like that. Hnng, you feel so good. 

Kai shot out of bed in a cold sweat, “Fuck,” he whispered, running a hand through his hair, as he  hopped out of bed. He walked to the bathroom and flipped the light on, looking at his reflection as he splashed cold water on his face. 

“This isn’t good.” he whispered to himself, as visions of Izuku below him swirled in the dark recesses of his mind, he looked down at his tented boxers, “This is definitely, not—good.” 

With a frustrated sigh, he went back to bed, shimmying his boxers down to deal with his arousal. Grabbing his small bottle of lube from his nightstand he laid out in bed, stroking himself and closing his eyes, gulping as the thought of half closed viridian eyes and lush green hair below him, mouth agape moaning, “ Sensei please .” 

His muscles tightened, jaw clenched as he let out a groan, releasing into his hand. Grabbing a kleenex off the nightstand he wiped his hand and threw it in the trash, rolled over and tried to sleep. 

Kai awoke the next morning brows furrowed in disgust. He felt sticky and wet. Peering under this comforter his eyes widened in disbelief as he jumped out of bed in horror.


He saw the wet spot in his bed, a wet dream. He had a fucking wet dream. How in the fuck? He quickly showered and dressed before stripping the offending sheets down and throwing them into his washer by the garage. 

“I’m disgusting. A terrible disgusting human being. Who lusts after their student!? Over one phone call? He barely even said anything!” Kai berated himself as he stress cleaned his home, mopping the floor with vigor. 

He spent the rest of the day grading papers, preparing lectures, but the sound of Izuku’s voice interrupted his thought process from time to time. 

Resting his head in his hands with a sigh, “I’m doomed.” 

He tried to keep himself occupied the rest of the weekend, only to be plagued by more wet dreams and more jerk-off sessions in the middle of the night. By the time Monday rolled around, he was exhausted. 

He went into his class and pulled out his computer and lecture notes, as students filtered in. 

“Good morning, Sensei!” A bright cheery voice called out to him. 

Kai looked up to see his dreams incarnate walk in, all sunshine and rainbows, clearly mocking his current state. And what’s worse, he had the audacity to smile so brightly and innocently at him. 

“Izuku,” he said flatly. 

Izuku cocked his head, “Sensei, you don’t look so good. Should I take care of you?

Kai snapped his gaze to Izuku, “What did you say?” 

“Uh, I said, you don’t look so good. Did you not sleep well?” 

“Ah,” Kai felt heat rising to his cheeks, “I’m—no. I didn’t. I’m pretty tired.” 

“Oh, I’m sorry to hear that! I can take you to bed .”


“Sensei,” he said slowly, “I said, I’m sorry to hear that. Please get some rest!”

Kai swallowed, nodding, they still needed to talk about his grade, “Sorry about that. Anyways, Izuku. Office hours today, we never finished our conversation on Friday evening.”

“Friday evening? But, I came in the early afternoon?”

Kai’s eyes widened, Izuku didn’t remember their phone conversation. 

“Ah, I’ll be there, Sensei. I’m really sorry I ran out on you the other day too!” He quickly bowed.

After he took his seat, Kai shortly started the day’s lesson; his eyes drifting over every so often to catch Izuku’s concentrated gaze on the slides on the screen. Each time he did, Kai saw Izuku swipe his lip unconsciously with his tongue, or bite on his lip as he scribbled his notes.

He found himself stuttering when Izuku did these movements, or anything that looked a little too erotic. 

Kai beat himself up internally, he hated how he was starting to notice his growing attraction escalate during lecture. 

How was he going to survive office hours? 

He dismissed class early, his brain too fogged over with thoughts of green. He holed himself up in the office, going over assignments, counting down the time till Izuku showed up for office hours. 

Like deja vu, a tentative knock was heard at the door. 

“Come in,” he called. 

Izuku walked in again, bashful and pink flushed cheeks. He paused at the door and Kai sighed, getting up once more to sit at the edge of his desk like last time. 

“Have a seat, Izuku,” he gestured to the chair in front of him. 

Without having to be told, Izuku remembered to shut the door before taking the seat he was offered. Izuku started to fidget again, unable to meet Kai’s eyes. Kai felt his eyebrow twitch in irritation and before he could say anything.

“I’m sorry for running out. I really am!” Big round green eyes pleaded with him, and Kai felt his heart skip a beat. 

“I didn’t even understand what you were saying,” he said exasperatedly, “and then the phone call—”

Izuku cocked his head innocently and Kai cursed his adorableness under his breath, “Phone call?” 

“I called you that evening,” he closed his eyes in annoyance and arms folded across his chest, “and—”

“—You called me?” Izuku squeaked, licking his lip nervously. 

Kai’s ground his teeth, the cute little squeak made his thoughts go south.

“—I’m sorry Sensei! I-I was,” he blushed, “I believe I was drinking that night. I was just so, embarrassed—” 

When Kai opened his eyes again to address the teen, his eyes focused on Izuku’s pouty pink lips that were mumbling about why he was getting drunk. Izuku nervously ran his tongue across his lips, leaving them glistening. 

Kai moved before he could think, surging towards Izuku and cupping his cherub face in his hands as he connected their lips together. 

Soft, sweet, a hint of cherry lip balm on his lips. Kai groaned at how perfect Izuku’s lips were slotted perfectly against his. When the latter froze, Kai realized the error of his ways. 

He broke apart, disconnecting their lips and pulled back. 

“I’m sor—” 

Before he could finish his apology Izuku rushed forward grabbing Kai’s face and fiercely kissed his professor back, pushing him up against the edge of the table. Golden eyes widened as Izuku’s tongue beckoned him to open his mouth to delve deeper. 

Kai closed his eyes, resigning himself to what was transpiring, wrapping his arms around the younger man’s lower back. 

His student pulled back in a flushed daze, and Kai could see the constellations of star-like freckles that adorned his cheeks like gold. The flecks of gold that flickered in viridian eyes, starting to blink rapidly before morphing into panic. 

“Oh my god,” Izuku said, pulling back, “Oh my God. Is this real, am I dreaming. Did I fall asleep in class again?” 

Kai grabbed Izuku by the shoulders to calm the young man down, “Izuku.” 

Izuku’s knees buckled and a whine came from his throat, Kai surprised by the effect he had on him, something flashed in his mind dangerously. 

He tilted Izuku’s chin up, so his golden gaze could look at Izuku’s properly. 

“This isn’t a dream,” he said darkly, before tilting Izuku’s face away to expose the expanse of his pale neck. 

Kai leaned in, lips attaching to his neck and sucking. 

“Oh,” Izuku gasped. 

Kai sucked harder on his neck, his tongue licking at its concentrated spot. 

“Oh, oh. Oh my God. This. This is really happening.” 

Izuku pushed Kai back, a determined look on his face, “Please. Please let me suck your dick!”

Kai choked on his air at the request. “Wow. No Hesitation.”

Izuku drops to his knees, hands on his thighs as they slide up reaching for his belt. Izuku’s expression suddenly turns sultry and seductive as he looks up adoringly at Kai, “I’d worship you.” 

Pride flared in his chest and lust burned in his gut at the way Izuku looked at him. 

“Then show me,” Kai said darkly, unaware he had this side of him. 

Izuku gulped, nodding obediently as he quickly undid Kai’s pats, and slid down his pants and underwear and wrapping his hand around his half-hard cock, pumping him and licking his lips like he was ready to eat a meal.

The young man’s cute pink tongue, that had teased him throughout all class, darted out, tentatively licking Kai’s tip. His tongue traced the crown, making Kai groan, his fingers curling around the edge off the desk. 

He rubbed the tip of his cock against his tongue, the heat of his mouth radiating onto him. Kai tilted his head back with a groan as Izuku took his time licking and mouthing at his hardness. 

Kai watched as lzuku’s lips closed around him, that slick velvet tongue working circles around him before sliding down and taking him whole. His hand reached for Izuku’s hair as he started to bob up and down. His fingers combed through soft green tresses, moaning every time Izuku sank deeper; cursing under his breath whenever Izuku’s doe eyes would look up at him so innocently yet filled with desire. 

Kai felt himself coming undone by those eyes alone. 

His mouth dropped open, the heat in his belly burning hotter as Izuku’s mouth brought him to the edge. 

Just as he was about to tip over, Izuku popped off, a trail of saliva still connecting them. 

Kai stared blankly at him, what just happened. 

“I can’t have you come yet,” Izuku said, “Not when you haven’t been inside me.” 

Kai’s lip curled in a smirk, Oh? How slutty. 

“Well, let’s fix that shall we?” 

Kai grabbed Izuku’s shirt pulling him in and kissed him roughly, the saltiness of his precome dancing on Izuku’s tongue. Izuku moans into his mouth as he pulls him close, his hands sliding down Izuku’s back to rest at his butt and squeezes. 

He unbuttons Izuku’s pants and slides them down, pulling his hardened cock out, lining it up with his, and starts to stroke both of them. 

“Oh fuck,” Izuku had mumbled against Kai’s mouth and groaning. 

He pulled away, presenting two fingers to Izuku, “Suck.”

Wrapping his lips around Kai’s fingers, he coated them with spit, sucking on them just as he had done on his dick. Kai pulled them out and instructed Izuku, “Bend over.”

Izuku switched places with Kai, bending over the desk and spreading his legs open. 

Kai marveled at Izuku’s backside, so plump, round, muscular. He groaned, how the fuck did I not notice how stacked he is?

Spreading Izuku’s cheeks he slid his slicked fingers up from his taint to his hole, the younger man stiffening at the touch, “You’re gonna wanna relax.” 

Izuku nodded as he looked back anxiously. Kai prodded at his hole, tracing the rim before pushing a finger in. Izuku was tight and hot; he bit his own lip in anticipation of sticking his dick inside. The younger man whimpered and whined, transforming to moans when he added another finger and scissored him open. When Izuku started to move his hips to add more friction he pulled out and Izuku made a pretty keening noise that dripped with desperation.

Settling behind Izuku he lined himself to his pretty pink hole and started to push in.

“Fuck,” he grunted out as he pushed against Izuku’s tight heat that sucked him in. Izuku’s walls clenched around him as he pushed deeper and deeper. He exhaled the breath he was holding as he fully sheathed himself. 

Izuku wiggled his hips, “You can move now, I’m okay.”

Kai withdrew with a shudder, and slowly worked his way back in. Kai felt himself already at the edge from the pulsating heat around him, but he’d hold on for as long as he could. Soon, he was rocking his hips shallowly against Izuku who moaned, and panted, but it wasn’t enough for Kai. 

He pulled out and yanked Izuku up by the collar of his shirt, “Turn around,” he demanded. 

Izuku followed his command and turned around, Kai hooking his arms under his thighs and lifted him up to sit on the table. He stole kisses from Izuku before laying him flat out across his table and pulling Izuku’s legs up, ripping off his shoes and pants in the process. Izuku’s boxers hung off his ankle as Kai pulled Izuku’s thighs flush against his abs. 

Reaching for his cock, he steadied himself and breached Izuku’s hole once more. He saw Izuku’s face contort in pleasure, his fingers grabbing the edge of the desk as Kai thrust deeply, jostling him up the table. 

This was what Kai was missing, to see this cute innocent face twist in pleasure. To see him thoroughly debauched: those flushed cheeks, heavy lidded eyes as he moaned and begged for his release, head lolling side to side. 

The desk screeched against the wooden floor as Kai fucked Izuku harder, his fingers digging into plush thighs so hard, bruises would be a nice reminder for Izuku. 

“Ah, Se-sensei, please!” Izuku cried, just like in his dreams.

Kai’s hips stuttered at the pleas, they sounded even more delicious echoing in his office, than the ones in his dreams. The slapping of their skin filled and bounced around inside the room. Izuku’s cries, his back arching off the desk, his papers falling to the ground as Izuku bucked against the desk. 

“Sensei!” He whined, “Close, so close!”

Kai dropped Izuku’s legs to the side, the younger man wrapped his legs around Kai’s thick waist.  He practically ripped the buttons of his shirt in haste to shed the extra clothing as he laid atop Izuku’s body, crashing their lips together as he reached even deeper. 

They moaned into one another’s mouths, Izuku’s hands running through along his back before burrowing into his reddish brown hair. 

“Fuck, that feels so good!” Izuku moaned against his ear, “Sensei, please! Make me come!” 

Kai groaned into Izuku’s shoulder, sweat dripping down his face as he pistoned his hips to bring his lover closer to the edge. 

“Call me Kai,” he panted out, locking eyes with Izuku. Izuku quickly nodded.

He cried out when Kai snapped against his prostate, tears leaked from the corner of his eyes as he whimpered how close he was. 

One final thrust had Izuku's nails digging into Kai’s back as he came, his semen ejaculating between them, as he cried out, “Kai!”

Kai bit down into Izuku’s shoulder as he came, the sound of his given name from Izuku’s lips pushing him over the edge. He buried himself deep and ground into Izuku as he filled him up. 

The two panted as they came down from their high. Kai rested his forehead on a freckled shoulder, before collecting himself and grunting as he got up. His legs were wobbly as he pulled out, come dripping out of Izuku. Kai wiped his forehead with the back of his hand as he slowly collected himself.

Izuku groaned as he tried to sit up; he tried to jump down from the desk, his knees buckled and gave out. Kai caught him by the elbow, “Careful.” 

“Hah, yeah,” He sighed with a lazy smile, he looked thoroughly fucked out, Kai helped him pull his boxers back on and sat him up on the desk again. 

Kai stood in between Izuku’s thick thighs, “Are you sure you’re okay?”

Izuku nodded as his heavy lidded eyes stared at Kai’s chest, he cocked his head, his fingers came up and started to trace the tattoo on Kai’s left pec, just over his heart, winding up to his shoulder, the edges barely visible below a collar. 

“This,” Izuku started as his fingers continued to trace the linework, his eyes flicking up to Kai, “This is what distracted me on my exam.” 


“The day of the exam, it was hot, you had unbuttoned the collar of your black shirt and I just, I couldn’t concentrate! I kept seeing the edge of your tattoo and then next thing I know my mind is drifting into the gutter. And your pants . Like, your pants were so tight and perfect on you, and I just, I couldn’t. Next thing I know the exam is over and—I never stood a chance when you looked so hot .” 

Kai smirked, crowding Izuku as he rested his palms on the table to lean down and chuckled, “So the saying is true.” 

Izuku cocked his head.

“It’s always the quiet ones that are the horniest,” Kai smiled dangerously as he continued, “Well, now you’ve seen and felt the real thing,” his eyes flicked down to Izuku’s plush lips, “It shouldn’t be a problem again right?” 

Izuku huffed a laugh, wrapping his arms around Kai’s neck, “Only if you promise to tutor me privately during office hours.” 

“I think that can be arranged. No one ever comes to office hours. So, how about we start that private lesson now?” 

“Oh yes.” Izuku wrapped his arms around his neck and pulled him in till their lips were millimeters start, “I’m definitely ready for my next lesson.”