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Since coming to True Cross Academy, Yukio had had to become accustomed to having time to himself. Back home, he’d never had the opportunity to be alone, too many people in too little space and whatnot. He hadn’t minded it so much, mostly because he hadn’t been aware that, sometimes, he just needed to be away from people, needed the quiet of an empty space to ease his mind.
The deserted halls of the exorcist school were a welcome distance from the hectic life of schoolwork and lesson plans. He loved teaching, probably even more than he liked learning. It helped reinforce his confidence, helped him gain the respect he’d been searching for most of his life. He hadn’t thought himself to be particularly authoritative when he was younger, but he found he liked running a classroom.
But sometimes, everything just got to be too much for him. He needed a break, needed to release some of the tension that had been building in his shoulders since they’d left for the mission in Kyoto. It had gone better than he’d expected it to actually, which was saying something considering the number of things that had gone wrong. At least they’d gotten Rin out without too much trouble. Mephisto was undoubtedly to thank for that one. The man was always getting them out of trouble.
Didn’t make Yukio want to be any friendlier toward the guy.
Pulling his keys out of his jacket pocket, he stopped in front of the demon pharmacology room. He unlocked the door and stepped inside, flipping the light switch and watching as the room was illuminated. The desks were still set up in the close semicircle he’d had the class arrange them into that morning, as part of his demonstration on pheromones. It had been a good lecture, even if his students had left the class in a confused cloud of sexual tension and on edge because of it. He’d allowed himself a moment of laughter once they’d all exited the room.
He really did like teaching, but things just got to be too much sometimes. While the class had had a good time during his displays of the effects of demon pheromones on humans, they’d obviously taken less away from it than Yukio had intended. Shura had told him not to worry about it later, landing a punch on his arm that he’d pretended hadn’t hurt at all. It hadn’t done much to reassure him.
Dropping his bag on his desk, he made his way to the blackboard that lined the front wall. He needed a drink. He was tired, but too uneasy to sleep. He could probably call Shura, tell her to bring something strong for him, and then the two of them could head to the basement for some rounds. He wasn’t necessarily fond of alcohol, but he couldn’t deny it was effective in treating random bouts of anxiety. And he had a higher tolerance than Rin. One wouldn’t hurt.
He started balancing equations instead.
He worked through a few easy ones, the kind he’d been able to do since he’d opened his first chemistry book, and moved up to ones that were more difficult. He wasn’t worried about being wrong; no one was there to see his mistakes. Not that he would make any. Chemistry was in his blood, it spilled onto the blackboard from his fingers as effortless as water flowed through the aluminum gutters on the sides of buildings when it rained. It calmed him, anything so solid and verifiable did. Too much of his life had been up to chance.
He wasn’t certain how long he stayed, mind and fingers working together to fill the entire blackboard with numbers and chemical symbols and pure reason. When someone entered the room, he felt it, felt the air stir and the pressure change. The hair on the back of his neck stood up, and his body tensed. It wasn’t a teacher.
It was a demon.
Reaching for his gun, he turned, his movements slow and deliberate. If there was one thing Gehenna had in common with Assiah, it was that a startled creature was always more dangerous than one that believed itself at an advantage.
He had never been so grateful for his quick reflexes than he was when he finally faced the intruder, just shy of pulling the trigger. He stopped just in time to save the boy perched on the edge of his desk.
He sighed, sliding his gun back in its holster and glaring at Rin over his glasses. “I could have killed you.”
Rin smiled, his fangs peeking out over his bottom lip. “Well, I’ll make sure to keep in mind that you were the first to have a change of heart.”
“What are you doing down here?” Yukio asked, shifting his weight to one hip.
Rin shrugged, and leaned back on his hands. One of his legs was bent up to his chest, while the other hung off the edge of the desk. “Kuro’s out cold and everyone from class is busy. I got bored.”
“So you just decided to take a leisurely stroll through the school, which is off-limits.”
Rin smiled again. “I figured if I was with a teacher, I couldn’t get in trouble.”
Yukio sighed again. He could think of no word other than insufferable to describe Rin, and he feared that might still be too generous. What Yukio wouldn’t give to have just one day, one complete, 24-hour day, free of Rin’s disruptive, irritating antics. Just one day that he didn’t have to get burned by Rin’s flames, or try to cover up some situation that was usually preventable. Yukio closed his eyes and rubbed at his temples, trying to relieve some of the pressure building there.
“I thought I gave you homework tonight,” he said, “Have you finished it?”
Rin didn’t answer right away and when Yukio opened his eyes again, he found an expression on the demon’s face that was equal parts perplexity and concern.
“Are you okay?”
“I’m fine,” he said, if only to keep Rin from asking too many questions. He was much too agitated for conversation.
“Are you sure,” Rin asked, “You look real pent-up.”
“I said I’m fine, Rin,” he stated more firmly. “Go back upstairs and do your assignment. Stop wasting time.”
He turned back to the blackboard and started on another equation, prepared to ignore Rin’s inevitable complaints and excuses. Rin was always coming up with some reason to avoid his homework. A lot of the time Yukio had to threaten to tie him to his chair. Once, he had to do more than threaten. Rin had all kinds of excuses, that his teachers didn’t like him and he was given an unfair amount of work, that he’d promised to study with Shima later in the day and he absolutely had to meet up with Shiemi first, that he couldn’t concentrate when he was hungry and didn’t spaghetti sound just lovely?
“I don’t understand it.”
Well, that was one he hadn’t heard before.
Yukio turned around again, his brow furrowed, and watched as Rin sat up straight again, biting his lip and looking down at the floor. It was a nervous habit he’d picked up as a kid that Yukio had once shared. He hardly ever saw it anymore.
“What?”
Rin sighed heavily, rolling his eyes and fixing Yukio with an exasperated stare. “I said I don’t understand the assignment.”
Yukio could have laughed, but he didn’t. He might have been frustrated with Rin, but he was still supposed to a teacher. He took a few steps toward the desk, placing his hand atop it and his other on his hip. “What don’t you understand?”
Rin’s cheeks flushed, and he dipped his head lower, turning it slightly so that Yukio couldn’t see his face. He was quiet, and for once Yukio was not grateful for the fact. He felt a pang of sympathy in his chest. He knew how embarrassing it could be to not understand something, the weight of it was excruciating. He moved in closer, leaning against the edge of the desk. His hand found Rin’s shoulder and squeezed.
“Hey, it’s okay. It happens to the best of us. I’ll help you.”
He felt his brother take a deep breath, and when he looked up again, Yukio could see the faintest trace of tears along Rin’s eyes.
“You will?” Rin asked, his voice small.
Yukio wanted to wrap his arms around Rin’s slim shoulders. “Of course.”
Rin nodded, but there was something off about the motion. When he spoke again, Yukio was surprised to hear his tone had gone from helpless and apologetic to accomplished, pleased. “Good.”
Yukio’s wrist was encased in warm, slender fingers. Rin swung his legs around to get up on his knees on the desk. The action made him as tall as Yukio, and the younger had no time to fight as Rin pulled him closer. Their foreheads nearly collided as Rin wrapped his arms around Yukio’s neck.
“Because I wouldn’t want to disappoint you,” Rin said, speaking against Yukio’s lips, “Sensei.”
“Nii-san, wha--,” his words were cut off as Rin pressed their lips together, a bruising force behind the kiss. Yukio made a slightly embarrassing sound deep in his throat, and suddenly the world was spinning and his back was up against something very flat and hard. When Rin pulled away and Yukio forced his eyes open again, he found himself lying on his back across the top of his desk, Rin straddled atop him.
“Seriously, Sensei, you’re so tense. Are you sure there isn’t something bothering you?” Rin said, his voice low, dangerous, as he slipped his hands beneath Yukio’s uniform jacket, spreading his fingers out over Yukio’s chest. Yukio could feel the heat of them through the thin fabric of his undershirt.
Swallowing around the lump in his throat, Yukio threaded his fingers through the fine hairs at the nape of Rin’s neck. The older boy hissed when his head was pulled back, his lips leaving Yukio’s suddenly.
“What are you doing?” Yukio asked, his voice barely a whisper.
Rin looked down at him, eyes half-lidded, smirk pulling his mouth up at the corners. His neck was stretched, the muscles and tendons taut, and he sounded a little out of breath when he said, “I just wanted to make you feel better.”
“Someone could walk in, you know,” Yukio said, tugging Rin’s head back just enough to have a good view of Rin’s throat working as he swallowed and spoke again.
“I locked the door when I came in.”
It wasn’t like that really mattered, Yukio thought to himself, knowing Rin knew it too. If anyone wanted to get into this room, it would only take a twist of the right key. He didn’t say anything though, just watched as Rin struggled to break free of the grip on his hair. Eventually, he settled, letting his head rest back against Yukio’s hands.
“You planned this,” Yukio noted aloud, unsurprised when Rin chuckled and said, “I’ve been trying to get you to notice me for weeks.”
And if it hadn’t been obvious that Rin was playing a game before, it all became clear with that statement. Yukio closed his eyes and shook his head in disbelief, his own laughter bubbling up from his throat.
“And what makes you think I want you,” he asked, playing along. It was impossible not to notice the way Rin’s shoulder’s tensed, and Yukio had a sudden, overwhelming urge to pull him down, to whisper and reassure and kiss the hurt away. It had taken a lot to get Rin to open up to him. He didn’t want to screw it up now, especially not for some game.
But just as he opened his mouth, Rin smiled again, and from this angle Yukio could see perfectly the sharpness of Rin’s teeth. He remembered the feel of them against his skin, digging painfully into his shoulder just the night before as he’d slipped his hand inside Rin’s pajama pants and jerked him off.
Yukio wasn’t sure what made him loosen his grip on Rin’s hair, but one minute he was staring up at his brother’s mouth and the next it was pressed against his own again. Rin’s tongue slipped between his lips and he moaned, sliding his hands down the length of Rin’s back and tugging the hem of his shirt up. Rin arched into him as he scraped his nails along the prominent ridges of the demon’s spine.
Pulling away just enough to kiss a trail up Yukio’s jaw and nip at his ear, Rin gasped, “I think we both know you want me, Sensei.”
And to deny it now would be to tell a boldfaced lie. Even if they had never done anything like this, if Rin had no prior knowledge of what could ultimately make Yukio come completely undone, his erection was enough to show that he did, indeed, want this, want every part of it, even if it was sometimes hard to admit to himself.
Rin’s shirt came off with minimal complication, getting stuck around his neck only for a moment when Yukio bit down on his lip and refused to let go. Rin laughed as he sat up, fingers flying to his own belt buckle and smirking down at Yukio like he knew Yukio was aching for it now. And Yukio was, his hands running up Rin’s chest like he couldn’t stand not touching him, brushing over Rin’s nipples and making the older boy gasp, eyes fluttering closed. When he passed the fingers of one hand over Rin’s lips, the older boy’s tongue flicked out to run over the tips.
“Suck them,” he said, inhaling deep as Rin’s lips fell open and he slid his fingers inside. Rin’s mouth was impossibly warm, his soft tongue a severe contrast with his sharp teeth. The feel of it made Yukio’s stomach bottom out, his blood rushing suddenly south. He thrust up involuntarily, the friction of his cock rubbing against his pants and Rin’s ass enough to leave him breathless. Rin sucked on his fingers with the same enthusiasm he had when he was sucking Yukio off, swirling his tongue over the pads at the tips and hollowing his cheeks.
And Yukio thought he would come right there, from just the sight of his brother’s lips around his fingers, the feel of him grinding back like he needed to be fucked just as badly as Yukio needed to fuck him. He had never expected to be so taken with the older boy, so affected. But he was, and Rin used that to his advantage too often.
A sudden shifting had him tearing his eyes away from Rin’s mouth to where Rin had finally worked his pants low on his hips. His slender fingers were wrapped in a loose fist and he was thrusting up into them, obscene and shameless.
Yukio sat up suddenly, tugging his fingers free of Rin’s lips, loving the sound of his brother whimpering, and batting Rin’s hand away from his cock. He wrapped his own slick fingers around it, pumping quick and hard. Rin let out a sound that was stuck somewhere between a moan and a growl and threw his head back. His skin was flushed a pretty pink and was so warm to the touch Yukio might’ve wondered if he was feverish. But he knew better, knew that any time Rin was excited, his blood heated, simmered just under his skin, preparing for the heat of the blue flames that would consume him if he weren’t careful.
It had happened once. He’d lost control. It had been right after they’d moved into the dorm together, and Rin had been agitated and needy for days. Yukio had held him down that night, one hand wrapped around his thin wrists, the other pressing his chest into the floor. The flames had come so suddenly Yukio had panicked, forgotten for a moment what to do, and it had taken the pained screams spilling from Rin’s lips for him to come back to himself, to start whispering the incantations in between the reassuring kisses he placed along Rin’s spine.
They’d been careful since then.
He skated a hand around Rin’s neck, cradling his head as he sucked a purple spot onto Rin’s throat. The older boy whined high and broken, and said something that sounded vaguely like Yukio’s name, hands scrambling for purchase on Yukio’s shoulders. Frantic fingers tugged at his jacket, pushing it down his arms until he was forced to let go of Rin to shake it the rest of the way off. And then Rin was fumbling with his pants, the holster around his waist.
“Fuck,” Rin said, gasping like he couldn’t take enough oxygen into his lungs. He was desperate at this point, arching into any touch Yukio would give him.
Yukio lifted up off the desk when Rin shoved his pants down his hips a little, hissing when Rin’s hand wrapped around his cock, thrusting up into it. Sliding his thumb under the waistband of Rin’s pants, he said, “These. Off.”
Rin leaned forward, pressing their foreheads together again. Rin’s hair and skin were slick with sweat. Yukio watched a bead of moisture swell and slide down the length of Rin’s neck, pooling in the hollow of the boy’s throat. He sealed his lips over it as he pushed at Rin’s pants, sliding them down toned legs.
“Wait,” Rin gasped, catching his arm before he was able to toss the offending article to the floor. Rin thrust his fingers into one of the pockets and pulled out two aluminum packets. Yukio recognized the items instantly and scoffed.
“The things you are actually prepared for,” he said.
Rin grinned, “Only the most important.”
He let Rin roll the condom on as he tore into the sample packet of lubricant.
“Did you get this from the nurse’s office?” he asked, spreading some on his fingers.
“I had to,” Rin replied, scooting back up and bending forward. His words were stuttered and winded as Yukio slipped his fingers inside. “I didn’t have time to go back to our room.”
“You were that concerned,” Yukio deadpanned, taking his time in sliding his fingers in and out. Talking helped Rin relax, laughing even more so.
“Well, I didn’t want—ah—my teacher to b-be depressed. How can we learn anything if you’re always so—shit—uptight all the damned time?”
“Indeed,” Yukio responded, twisting his fingers up and curling them forward inside Rin. He watched his brother’s eyes roll and his mouth open in a silent scream and knew that Rin was ready.
Rin needed very little guidance straddling his cock, but Yukio held the backs of his thighs as he sank down, keeping him slow and steady. He didn’t even try to stifle the moan that ripped from his throat at the feel of Rin around him, warm and tight.
Rin chuckled against his mouth and said, “See, I knew you wanted me.”
Yukio’s only response was a sharp thrust upward, but it worked nicely to shut Rin up. Rin’s whole body tensed, a belligerent groan sounding low in his throat, and he buried his face into the junction of Yukio’s neck and shoulder. His teeth scraped the sensitive skin there and Yukio’s hand flew to the back of Rin’s head, holding him still as he forced his hips up again, shallowly this time.
It was all biting and scratching and panting into each other’s mouths after that, Rin lifting up on shaking legs, supported by Yukio’s hands on his hips, only to come back down, sending shocks of white across Yukio’s vision. At some point, Rin made a noise high in his throat, a lilting, desperate whine, and when Yukio asked what he wanted, what he needed, he said in a frenzied voice Yukio thought for sure he’d never heard before, “Touch me, please.”
And it took only three jerks of Rin’s cock for the older boy to throw his head back, moan breaking off in a sob, as he came over Yukio’s hand. The feel of Rin’s muscles clenching around him took his breath away, and he smothered his own cry against Rin’s neck, coming a moment later, riding out the aftershocks as he sucked at Rin’s pulse point.
Afterward, the room was still, peaceful. He let himself fall back across the desk again, trying to slow his heart, his breathing. Rin hissed as he pulled out, reaching down to pinch the condom off with trembling fingers. He chuckled at his brother’s disgusted face as he disposed of it in the waste bin under the desk. Then he cupped the back of Rin’s head with one hand, pulling the older boy down to kiss him. It was lazy and content and Yukio found his mind to be pleasantly blank.
Rin hummed against his mouth, and Yukio’s wrist was circled by something soft and warm. He recognized it instantly as Rin’s tail, having long since gotten acquainted with it. He felt Rin smile, subdued for the time being.
“Feel better, Sensei?” Rin whispered, and Yukio laughed again.
Yeah, he really liked teaching.
“We should get dressed,” he said, “before someone comes looking for us.”
Rin groaned. “I don’t think I can stand.”
Rolling his eyes, he slapped the back of Rin’s thigh to get him to move. It worked. The two of them slid off the desk and gathered their clothes up off the floor. He ended up throwing his jacket over the back of his chair, watching as Rin slipped his legs back into his pants.
Just as Rin was pulling them up over his knees, the door to the classroom swung open, three boys walking into the room with varying looks of confusion and frustration on their faces, and Yukio wanted to die.
Konekomaru was the first to notice the two of them standing at the front of the room, stopping so suddenly Bon almost tripped over him. Shima looked up as Bon grumbled about almost killing people, one eyebrow rising, curious but non-judgmental. And really, if anyone had to find out, Yukio figured Shima was the best they could hope for. When Bon finally looked up, his eyes grew wide and his mouth fell open.
And for the second time that day Yukio was thankful for his exorcist training and his quick tongue. He’d had quite a bit of practice getting himself out of uncomfortable situations.
“Well, Okumura-kun,” he said, furrowing his brow and crossing his arms over his chest, ever the calculating doctor, “I don’t see any reason for further concern. If you keep applying the ointment I prescribed, the swelling should go down in no time.”
He could tell Rin was trying to keep himself from screaming, but said nothing as he pulled his pants up over his hips and fastening them.
“Is there something I can help you with?” Yukio asked, addressing the group of boys that were still standing just inside the room.
No one spoke for a moment, still lost in the awkwardness of the atmosphere. Rin plucked his sword from where it had fallen off the desk and onto the floor, swinging it over his shoulder.
“It’s just…” Konekomaru started.
“We don’t understand the assignment, Okumura-sensei.” Shima finished.
As Rin doubled over in laughter, and the other’s watched his brother like they thought he might have actually gone mad, Yukio made the decision to talk to Mephisto as soon as possible. He was going to request some time off, find some place near the ocean. He was leaving.
And he was going alone.