AN: this was posted on AO3 on 3/8/2017. all characters depicted are of age to have and consent to sex. based on a dreamwidth prompt. my works are rated M for a reason. if you're not 18+, i suggest you go back. i will not be held responsible because you decided to go click-hungry.

and if i get one review about keith being trans in this fic, i'm going to laugh at you. i got one recently on a trans pidge fic and i'm not okay with it. everyone is more than free to imagine the characters however they wish, whether it be cis, trans, or non-binary. if you have a problem with that belief, then hop out of all my stories and leave me alone, because you suck.

AO3 tags: Teacher-Student Relationship, SHEITH - Freeform, Squirting, Trans Keith (Voltron), Cunnilingus, Desk Sex, Panty Sniffing

Waiting for class to end is never something that he does. When he teaches, he's excited to teach his students. His excitement is reciprocated by them and the time passes by quickly.

Now that he has something he's waiting for, time passes torturously slow. Shiro's eyes keep darting to the student who watches him intensely. Keith looks like he just snatched the bird right out of its cage. He looked ready to devour it and savor the taste. Only Shiro was the bird, and the idea has him biting his lip at the idea.

The bell rang, a shrill sound in his ear. He motioned for his students that they could leave and they eagerly escaped the room, not bothering to question why he was letting them go directly on time. Shiro strode to the door and closed it, locking it with a firm click. Grabbing the blind, he took once glance outside before pulling it down, cutting all sign of life in the room. Turning around gave him a sight. Keith sat on his desk, one leg crossed over the other, leaning back on his hands. That grin was still on his face, growing with every second. If he had another class to get to, he didn't look like he cared that he was about to miss it.

Shiro undid his tie and strode towards him, keeping his expression stern. When he got close, he leaned over him, hands on either side of Keith's hips. "You knew who I was that night."

"I did," Keith answered, bouncing his leg up and down, the side of his foot brushing against Shiro's knee.

"Do I want to know why?"

He shrugged his shoulders. "You're hot. I'm not the only one who thinks so. When I saw you there at the club, grinding against everyone that wasn't me , I knew I had to take my chance."

Shiro bit his lip. He was honest and he had to give him that. There was no lying his way out of this. He enjoyed what they did and he fucked into his hand last night thinking about it. How Keith felt around him and the way his lacy underwear felt rubbing against his cock and the back of his , how could he forget that night?

Grabbing him by his knees, Shiro parted Keith's legs and pulled him to the edge of the desk. He fit snugly between them, pressing his growing hardness against him.

Keith chuckled, wrapping his arms around his shoulders. "Round two?"

Shiro cut him off with a searing kiss, pushing him back until he laid down across his desk. His pants felt impossiby tight as he rutted against him. Moments of Saturday night came back to him and he groaned. His hands came up and undid Keith's pants, jerking them down his hips. Keith whimpered when he pulled away from the kiss, but Shiro groaned at the lacy pair of underwear he saw.

Nothing was stopping him from taking them.

Keith toed off his boots and shimmied out of his pants. He chuckled when the lacy material was thumbed, only to be yanked off and bunched up in Shiro's hand. Shiro thumbed at his clit before moving down and plunging his digit inside him. He was soaking wet and Keith moaned. "I kept thinking about all the things that you'd do to me… If you'd fuck me as wildly as you did in the club or more."

Shiro moved up his body and nibbled at his neck. More held so many other possibilities. Each one had his dick twitching. Waiting was the issue, though. Right now, he could just fuck Keith without a care in the world or he could fuck him with a little more finesse.

He went the route of finesse.

Kissing down his body, Shiro moved his shirt above his navel. He left marks along his pelvis, leaving one right after the other in no sense of style. The first taste of him had him groaning. He's imagined it so many times, eating Keith out until he was gushing in his mouth. He never thought he'd get the chance to do it. He could look through all the clubs in the city to try and find Keith again, but his own thoughts always brought him to the conclusion that Keith was nothing more than a one night stand. Like the rest of them.

But that was his thoughts and this was reality.

Keith was right here , laying on his back as Shiro ate him out. His fingers ran through his hair, coxing him to do more as he ground his hips against his face. Shiro eagerly obeyed, twirling his tongue around his clit. Keith's moans urged him on and his pants grew tighter. Moving further down, he pushed his tongue inside him, eliciting a loud moan out into the air.

Standing up quickly, Shiro shoved the underwear into Keith's mouth. He moaned, biting down on the lacy material. "Unless you do want to be caught, you'll keep that in. Understand?" Keith nodded his head, chest heaving. It was a shame. Shiro still wanted to feel and see that pretty mouth around his cock.

Another time and there will be another time now that he knows Keith is in his class.

He pulled Keith to his feet and turned him around to face the desk. Keith placed one knee on top of it and leaned forward, offering his dripping cunt to Shiro. Wiping his mouth, he stepped forward, wrapping his arm around his waist. He shouldn't. He doesn't have a condom. There are too many risks with this.

Keith rubbing his puffy lips against his cockhead makes his mind go blank and he plunges himself in.

The underwear in his mouth isn't enough. Keith is vocal even with a gag. Shiro wants to hear it. He wants to hear every moan that will spill from his mouth. Later. When he has him in his apartment and in his bed.

Shiro leaves open mouth kisses on his neck as he starts to move. Last time, his thrusts were frantic; a need to get a quick fuck in and release a month's worth of pent up frustrations. Now, it was all about taking Keith in. Feeling how his body shuddered as he pulled out and pushed in in an agonizingly slow pace. Watching him as he lowers his head and whimpers, pushing his hips back against him to make him speed up.

He grips his hip and stops him, pushing him closer to the desk. Papers crinkle under his hand as he leans forward. "None of that now…" Keith whimpers and he eats it up, still moving at a slow pace that's driving him mad.

Keith is still whimpering and trying to fight against his grip. He's clearly not someone who wants a slow and tender fuck. At least, not now. And Shiro can agree.

Pulling out slowly, he grabs his hips with both hands and surges forward hard. Keith fumbles forward, a moan piercing through his underwear. Every thrust into him has him shouting, body lax as he lays across the desk, letting Shiro use him. Shiro ran his hand up his back and tangled in those wonderful black locks that came loose from his ponytail. He pulled Keith back to him until they were pressed together. His hot breath brushed his ear, making his entire body shudder.

"You like that, don't you?" Shiro whispered. He left a mark on Keith's neck, groaning at the contrast on his skin. "Fucked senseless all over my workspace and making an absolute mess out of it." Stilling himself deep inside Keith, he reached down to his cunt and rubbed his thumb over his clit. It made him spasm around Shiro's cock and he loved it.

He could only imagine the kind of torture that Keith must be going through. Unable to thrust back onto him and stand there while Shiro assaulted his sensitive clit. His hands reached for his wrist, nails digging into his robotic arm. As something to ground himself or to get Shiro to stop, he didn't know. Stopping wasn't a thing he was going to do. He thrust into him, returning to his pistoning pace that had Keith's eyes rolling to the back of his head.

Keith garbled something that he couldn't hear and he wished he did. Before he knew it, his cunt spasmed hard around his cock as he cummed, squirting over the papers that littered the desk.

"Did you just…? Oh, fuck …!" Shiro bit down in the junction of Keith's neck, hips rolling to a stop as he cummed inside him. He hadn't meant to, but seeing Keith squirt because he fucked him good had him losing all sense of control. Hell, Keith in general had him lose all his control.

They slumped forward, bracing themselves on shaky hands. Keith's shoulders rose and fell, his body shuddering with each tender kiss that Shiro delivered to his shoulder. He raised his head, teary eyes pleadingly looking at him. Shiro reached up, unraveling the underwear from his mouth.

"I'm keeping these," he muttered, his voice raspy.

Keith smiled. "What am I going to wear for the rest of the day, professor ?"

"Words like that are going to get you fucked again. And don't you try to start it." Keith pouted and it shouldn't have looked as cute as it did. "If you want them, meet me for dinner tonight."

Biting his lip, he nodded. "I'd love to."

They parted ways and Shiro tucked himself back in. He watched Keith from the corner of his eye as he gathered up the papers, his cum sliding down his thighs. It was a beautiful sight. His hand touched a wet paper and he pulled his hand back. He read the paper quickly, chuckling at the name he saw.

Keith finished dressing, redoing his ponytail. He turned to Shiro, grinning at him. "Is that all, Shiro?"

Shiro slid the paper closer to him. "It is. Meet me at the front gates at five."

Nodding, Keith turned on his heel and headed for the door, unlocking it before exiting. Shiro sat back in his chair, bringing the spit soaked underwear to his nose. He fingered the wet paper, stroking Keith's name. To think he left it behind. Maybe it's a bit funny that, out of all the papers on his desk, that Keith would soak that one through. And he was suppose to take it home with him.

But it smelled like Keith. It smelled like Keith just as much as his underwear did.

Shiro took a deep sniff, closing his eyes to savor the moment.

He was so screwed.

AN: since this is an old fanfic, i didn't bother cleaning it up. i had sworn off THIS PLACE, but i decided to give it a try again. feel free to check me out on twitter/tumblr (perversionsao3) or on Ao3 (perversions).