Tamaki leaned in and sealed their lips together. Mirio hesitated, hands frozen stiff in the air. He was waiting for Tamaki to panic, to pull away.
When he didn't Mirio dared to kiss him back, letting his hands find their way to the curve of Tamaki's waist and under the hem of his shirt, fingers pressed to bare skin. Tamaki made a noise deep in the back of his throat, a noise Mirio had never heard.
He pulled back long enough to admire Tamaki's expression, the one he saw at night in dreams he didn't care to tell anyone.
The open-mouthed, pupils-blown-wide Tamaki that no one got to see but him.
Things had never gone very far between them, not that Mirio was upset about it. They had been friends for ages, but this for only a couple of months. Physical intimacy wasn't something Tamaki took to easily. Mirio had known that since day one, but whether it was a light touch in the hallway or a lingering kiss in the privacy of their rooms every little victory with Tamaki was rewarding. It was all a part of Tamaki he had thought he would never see.
That was where it always ended, with Tamaki de-escalating their touches until he finally pulled away. Some fear would come over him, something he could never articulate to Mirio. His anxieties always bested him, leaving him shaken and apologetic as Mirio soothed and assured him.
In this moment though, something was different.
Tamaki's expression, usually shy and guarded, was like nothing he had seen before. It was vulnerable, and the dizzyingly dark pools of his eyes showed no trace of hesitation.
Tamaki's expression overwhelmed Mirio's senses, and his hands dropped to Tamaki's waist and lifted him with ease into his lap. Tamaki looked down at the place where their uniformed chests were pressed together, rapid breaths rising and falling against each other. His legs were straddling Mirio's waist, hands pressed against the other's chest with gentle force as if deciding whether to push away.
"Is this okay?" Mirio asked, head tilted to peer into Tamaki's face. Part of him expected Tamaki to pull away, to crumble in on himself as he always did.
Instead his cat-like eyes narrowed, painting an expression that would be close to resolve if it weren't for the slight tremble of his lips. He nodded, ink black hair bouncing.
Mirio senses weren't really intact enough to keep track of how things happened, lost in the sound of Tamaki's labored breaths, the taste of his wine-sweet breath and the warmth flowing between them.
It was only when Tamaki's voice emerged as a shuddering breath that Mirio snapped to attention, suddenly aware that there was more than heat but pressure building between their tightly-pressed bodies. Tamaki's arousal was pressing insistently against Mirio's stomach. Mirio found his own hips rocking gently against Tamaki's, heat flooding down his spine and pooling in his groin.
Tamaki's face was drawn down into a focused expression akin to worry, except that his lips were parted and panting, moisture shining at the corners of his mouth. His face was flushed and burning when Mirio pressed his hand against it.
"Should I stop?"
The other boy shook his head rapidly, dark hair fanning out over his face, and Mirio suddenly realized that Tamaki's downward gaze wasn't just an attempt to avoid eye contact but trained on the place where their bodies met.
He had never seen the other boy's emotions so exposed.
It was hot as hell, and Mirio couldn't help but pull Tamaki's waist tighter against him even as his chemical-flooded brain struggled to make sense of the situation.
He broke the seal of their kiss to trail his mouth along Tamaki's jaw and down his neck. Tamaki's thin fingers clutched at Mirio's arms as he pressed his forehead in the hollow of Mirio's collarbone.
A shaking gasp spilled from Tamaki's throat.
"Ah... Mirio..."
The sound of his name made Mirio swallow against a throat dry from his own shallow breathing.
Tamaki's hot breath was spilling against Mirio's breast, sending shivers down his spine and straight to the place where their swollen members strained against each other's.
"I'm... It's..." Tamaki's voice was coming out in broken phrases, and the sound was doing devastating things to Mirio's pulse. But he could also hear the familiar tremble of anxiety in the other's voice, and slowed his movements enough to focus on the other.
"Are you close? Should I stop?".
Tamaki was silent for an agonizing moment, just the sound of their labored breathing filling the room.
Mirio began to panic.
"Tamaki, look at me…" He made to grab Tamaki's shoulders, but Tamaki burrowed his face against him.
"Just, don't look. It's embarrassing." Tamaki murmured. Mirio could feel the heat of the blush coloring Tamaki's cheeks, even if he couldn't see it.
"Don't stop," he breathed, his lips tickling Mirio's throat.
"Tamaki…" Mirio hesitated.
"Please… "
His voice trembled, but even so there was a firmness in his tone that was undeniable. That was all Mirio needed to hear to let go of what little control he had clung to. His fingers curled against Tamaki's hipbones and pinned the smaller boy helpless to the rocking of his hips.
Face buried in Mirio's neck, Tamaki's ragged breaths turned into softly muffled groans that rang louder than life in Mirio's ears. He felt Tamaki's body start to move in its own rhythm, chasing after that moment of relief. Mirio buried his face in Tamaki's soft dark hair and let his own movements slow as Tamaki came undone, trembling in his lap.
There was silence between them, punctuated by Tamaki's rapid breathing. He was still clutching on to Mirio, as if scared of what would happen when he let go.
"Come here," Mirio soothed, pulling him reluctantly into view.
Tamaki's gaze was already downturned, avoiding the other's. His expression was beautifully bothered, damp hair sticking to his forehead.
"You look so good."
Mirio hadn't really meant to say it out loud, but he was glad he did when Tamaki's gaze immediately darted up to his. The moment his pale face tilted up towards Mirio's, the blonde planted a kiss on his lips.
"Mirio..." Tamaki's voice was barely a whisper.
"Hm?"
"I…" he struggled over the confession, as if the words were stuck behind his teeth. "It felt good. Thank you."
Mirio was watching him with rapt attention and an ever-growing grin.
"You don't need to thank me for anything," he soothed.
"I know I make things hard for you..."
"Stop." Mirio interjected, expression quickly souring. "Don't say that."
They had been over this before. Tamaki had always been overly apologetic and way too hard on himself, but it wasn't until Mirio had gotten close to him like this that he had seen the depths of that insecurity.
"I just want you to know I'm sorry-"
"You don't have anything to be sorry for."
Mirio's tone was decisive and before Tamaki could say another word he got to his feet on the mattress, knocking a startled Tamaki off of his lap.
"You feel good, right?" Mirio asked.
"Yeah," Tamaki stammered, gazing up at him from the mattress.
"Then I'm happy," his smile was dazzlingly genuine.
It made Tamaki's heart give a last frantic kick.