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The lab hummed like a beehive eating electricity.
Donnie stood in the center of it, lit by the glow of seven different monitors, goggles pushed up into a purple halo. His claws flew over a touch surface, thumbs tapping, the bō leaning within arm’s reach like a polite sentinel. Screens scrolled: waveform graphs, error logs, a schematic with more red than was ideal. He’d been going for nineteen hours. Maybe twenty-one. Numbers got slippery when you stopped treating them like anchors.
He was past tired. He was airborne. That jittery, crystalline edge of wakefulness that made everything feel too loud and also like the only place he could think. He could feel his heartbeat in his fingers and toes and behind his eyes. Sleep felt like a language he used to speak.
Footsteps padded in without stealth. Blue bandana tails flicked at the door like a flag.
Leo leaned in the doorway, arms folded, casual slant of his hip telegraphing non-threatening intervention. “Hey, Dee. Got a second to talk about your, uh, relationship with circadian rhythm?”
“Estranged,” Donnie said, not looking up. “Irreconcilable differences.”
“Mm. Maybe we can mediate.”
Donnie made a noncommittal sound and swapped a kernel value. The waveform leapt, sulked, then begrudgingly smoothed a hair. “Progress.”
“Did you eat?” Leo asked.
“I consumed calories.”
“Did you lay down?” Leo countered.
“I am sitting with purpose.”
Leo pushed off the door and came closer, the air changing in that indefinable way when Leo put his attention on you like a hand on your shoulder. “And how long have you been actively feuding with the idea of closing your eyes?”
Donnie considered lying. Gave up. “Several hours.”
“Try twelve more.”
Donnie’s mouth tipped sideways. “The plan is elegant. If I ride the wakefulness long enough, I’ll collapse and sleep for ten hours straight, thus resetting my clock.”
Leo grimaced. “You’ve tried that plan before.”
“It works.”
“You also hallucinated a conversation with the humidifier.”
“The humidifier was surprisingly empathetic,” Donnie said primly.
Leo snorted. “Come up for air, genius.” He slid in close enough to bump shoulders. “Take a break. I promise your circuit’s not going to run off with a toaster while you’re gone.”
“The toaster is not its type,” Donnie muttered, but the cartoon of it unstuck something at his sternum. He leaned back, rolling his neck once, twice. It ached. The ache came with it that buzz that said bed except his brain was already shaking its head no.
Leo clocked it. He always did. “Okay. We’re going to do this my way.”
“Your way is chaos.”
“My way is guided chaos,” Leo corrected, already herding him out of the lab with soft, inexorable pressure. “First: hydration. Second: environment hacking. Third: twin-powered nonsense.”
“What does that entail.”
“You’ll see.”
They cut through the lair’s hall—concrete cool underfoot, the pipes humming as the city breathed above them. The living room lights were low; Mikey had strewn star-shaped pillows everywhere because he was on a “cosmic comfort” kick. Raph’s weights sat in neatly terrifying stacks.
“Hydration,” Leo announced, handing Donnie a cup. “Now we make the lair behave.”
“The lair is already behaving,” Donnie said, but sipped. The cool water made his stomach flex. He put the cup down with mechanical precision.
Leo dimmed the lights another degree. “Less prison yard, more planetarium.”
“This will alter my melatonin production,” Donnie admitted. He crossed his arms to reclaim a point. “Marginally.”
“Marginal is my middle name,” Leo said, clicking on Mikey’s star projector. Soft constellations bloomed across the ceiling in pale blues and greens. “Step two: body trickery.”
“I don’t trust this.”
“You will,” Leo said, dropping onto the floor. “Sit.”
Donnie hovered. Leo patted the mat. Donnie exhaled like a man signing a treaty and folded down beside him.
Leo started with stretches—a deft, practiced series they’d been doing since they were small: neck rolls, slow shoulder circles, spinal twists. Donnie followed reluctantly, every movement uncorking micro-tension he hadn’t noticed until it screamed on exit.
“This is stupid,” he muttered, as something finally let go under his shoulder blade. “And effective.”
“Two things can be true,” Leo said, gentle smugness in his voice. “Now: breathing.”
“If you tell me to imagine a beach, I’m leaving.”
“You’re in your lair, don’t worry.” Leo slid closer, their knees touching. “Four in, six out. I’ll keep time.”
Donnie resisted for twenty seconds. Then he did it. Counting gave his brain something to hold. Leo exaggerated his own breaths until Donnie’s lungs synced up like they’d been waiting to for an hour. In, out, difference you could measure. The spin inside Donnie’s chest slowed.
“Name three things you can hear,” Leo said quietly.
“The hum of the humidifier. The projector fan.” Donnie listened. “Your bandana tails moving when you breathe.”
Leo laughed under his breath. “Ninja senses, I admire you.”
“Two things you can smell?”
“Metal,” Donnie said, surprising himself. “And… Mikey’s cinnamon… no, ginger.” He corrected himself with unnecessary precision, cheeks heating at getting it wrong first try.
Leo didn’t call it out. “One thing you can feel.”
Donnie turned his hand, caught Leo’s fingers without looking at him. “Warm,” he said, and felt the word land in his own body like a weight that made him steadier instead of sinking.
They sat like that. It helped. It didn’t flip a switch; it eased a dial. Donnie could feel the wakefulness still—not a wall, exactly, but a pane of glass between him and sleep. He could see through it and knew the route, but his body wasn’t moving.
“Okay,” Leo said softly. “Step three: twin-powered nonsense.”
“I fear you.”
“You should,” Leo said brightly, and tugged Donnie up. “Come on.”
They wandered the lair. Leo made him do the silent obstacle course—on soft feet, slow. Donnie corrected three of Leo’s form choices on principle. Leo did a dramatic point when Donnie wobbled on a balance beam and Donnie glared until Leo backed off, hands up. They passed the kitchen; Mikey had left a sticky note on a plate that read “emergency midnight banana bread.” Donnie sniffed it, then looked offended at himself for wanting it. Leo split a piece for them. The sugar barely hit Donnie’s tongue before his body went too sweet and filed a complaint, but the ritual of it softened the edges.
“Confession,” Leo said as they walked again. “I’m improvising.”
“You don’t say.”
“Stop thinking about sleep,” Leo advised. “Think about… recalibrating your brain. If you call it sleep you’ll get oppositional.”
Donnie glared, because he hated how seen that made him feel. “I am not oppositional.”
“You’re a masterpiece of contrarian engineering,” Leo said fondly.
They ended up in the dojo. The mats had the faint smell of rubber and sweat and old wood. Leo crossed, rummaged in the old audio cabinet, and came up with a battered portable speaker Mikey had bedazzled in a weak moment. Leo fiddled with his phone.
“No whale sounds,” Donnie warned.
“No whales,” Leo promised. “Just this.”
A soft wash of ambient sound filled the dojo—distant rain (not the cold kind), a low synth, something like wind through chimes but not annoying. Donnie felt his jaw unclench another degree.
Leo sat against the wall and patted the space in front of him. “Come here.”
Donnie stood in the middle of the mats and resisted. The projector stars had crept into the dojo from the hallway, ghosting faint galaxies across the ceiling. He suddenly, acutely, did not want to be alone in the middle of the floor with his own wakefulness.
He huffed and crossed to Leo. “If this is an attempt to entrap me in a cuddle, I will file a formal complaint.”
“Please do,” Leo said cheerfully. “I love your paperwork.”
Donnie sat with his back to Leo, unsure where to put his hands. Leo solved it by sliding his arms—careful, unhurried—around Donnie’s midsection and pulling him gently back until Donnie’s shell met Leo’s plastron. Leo was warm. He adjusted so Donnie’s bandana tails weren’t squished. He spoke into Donnie’s left ear, soft. “Better?”
Donnie’s throat worked. His first instinct was to flee. His second was to stay. The second won by an inch he was proud of. “It’s… acceptable.”
“High praise.”
Leo’s hands settled—one over Donnie’s middle, the other loose across his ribs. Not trapping. Not pushing. Just present. The ambient music breathed with them. Donnie could feel the microshifts of Leo’s chest at his back, the way his breath rearranged the air around them.
“Too tight?” Leo asked quietly.
“No,” Donnie said. He surprised himself with how fast the answer came. “Not tight enough.” The last two words slipped out without his consent. He tensed.
Leo tightened by a fraction. “Say when.”
Donnie didn’t. He let himself lean.
“Now,” Leo murmured. “I promised nonsense. Do you want a story? A lecture? I can do both.”
“Lecture,” Donnie said, because that felt safer than story. “Teach me… something boring.”
“Boring,” Leo repeated, appalled. “I only know fascinating things.”
“Then the end result will be failure,” Donnie said, and his voice had softened into the kind of snappish that meant I’m tired and worried and trying not to be.
Leo humored him anyway. “Fine. I’ll talk about… the proper way to fold a fitted sheet.”
“False. There is no proper way.”
“Correct,” Leo conceded. “Then… hm. The history of our worst mission nicknames?”
“Pass.”
“The theatrical merits of Mikey’s pancake flips?”
Donnie exhaled something that wasn’t a laugh but lived nearby. “Go on.”
Leo started talking, low and warm, about nothing and everything—shared tiny memories, the way Mikey’s flips had gotten higher as he’d gotten happier lately, the time Raph pretended to be a coach and yelled about maple syrup like it was a team sport, that one night they all fell asleep on the couch and Splinter put a blanket over them without waking them up. His voice folded around Donnie like blankets never could. It didn’t matter what he was saying. The rhythm did the work.
Donnie’s mind kept trying to sprint—what about the red in the schematic, what about the oscillation, what about the variable you left on the bench—and Leo’s hands answered every time by moving just enough. One stroked idle patterns—barely there—over Donnie’s plastron. The other skimmed up, fingers turning gentle where the edge of soft shell met skin. Donnie shivered at the feather-light touch and hated that he liked it; and liked it anyway.
“Okay?” Leo breathed, catching the shiver.
Donnie nodded once, small and sharp.
“’Kay.” Leo’s fingers rose to Donnie’s cheek. He didn’t cup it. He traced along the edge of his jaw and the line of cheekbone once, twice, the lightest touch, like saying hello to the nerves there so they’d stop buzzing mad. Donnie’s breath snagged and then loosened. He let his head tip back an inch against Leo’s shoulder.
“Tell me three things you can see,” Leo whispered.
“Ceiling,” Donnie said. “Stars. Your stupid reflection in the window.”
“Flattering,” Leo said.
“Two things you can feel?”
“Your hand,” Donnie murmured. “And… the way the air moves when you breathe.”
Leo went quiet at that, and when he spoke again it was like he’d moved closer even though he hadn’t. “One thing you want right now.”
Donnie’s mouth opened. Closed. His pulse thumped in his ear. The truth hovered and then landed, light. “To stop thinking,” he said, tiny. “And not be alone.”
Leo’s arms tightened, just enough. “I can do both.”
He did.
Donnie discovered that if he let Leo bear three percent more of his weight, his spine unhooked one vertebrae at a time. If he tried to speak, the sentence caught in his throat; when Leo spoke, the words soothed without needing content. The ambient sound turned the dojo into an aquarium without edges. The projector’s stars drifted like they were unsoldered.
“Breathe with me,” Leo said again, the sentence so familiar it no longer made Donnie bristle.
Donnie obeyed. He hated obeying in principle; he liked obeying Leo in practice. He followed his twins warm rhythm—slow inhales, longer exhales—and somewhere in the second set his body conceded.
“Fight me less often,” Leo murmured, half a joke, half a plea.
“Unlikely,” Donnie said, and heard how slurred it was.
Leo smiled into his bandana tails. “Worth a shot.”
Minutes went soft. Donnie’s hands, which had been in a precise neutral position, curled in slow, unconscious increments until his fingers were resting over Leo’s forearm. Leo’s thumb drifted back to Donnie’s cheek, stroking faint arcs, barely-there. The touch made Donnie’s face feel like it was properly attached again.
“You can sleep upright,” Leo said quietly, like he’d just remembered it for him. “Your body knows how.”
“That is… unverified,” Donnie mumbled.
“Then we’ll make it verified,” Leo said cheerfully.
Donnie’s cheek slid a millimeter more into Leo’s fingers. He felt Leo’s breath change—an inhale that stuttered on something soft—and pretended not to notice.
“Leo?” Donnie said, suddenly, because he needed to burn it off: the part that fought help just to hear it offered again. “If you let go, I’m going to ricochet off the ceiling.”
“Good thing I’m not letting go,” Leo said.
“Promise,” Donnie said before he could stop himself.
Leo’s laugh turned into something not-laugh in the middle. “I promise.”
Silence. Breathing. A tiny, embarrassing sound escaped Donnie when Leo’s fingers traced his cheek again—so quiet Leo could have pretended not to hear it. Leo didn’t pretend. He did it again. Donnie didn’t stop him.
“I’m going to say something sappy,” Leo warned, voice thread-fine.
“Please don’t.”
“Too late,” Leo said. “You’re safe.”
Donnie made a face. It didn’t reach the parts of him that needed to hear it. The parts of him that believed logic more than lullaby heard safe said in a way that sounded like a lock turning the right direction.
He let himself go heavier. Leo hugged him from behind like a seatbelt and a horizon and a home.
The projector stars slid across the ceiling. The ambient music kept pretending to be rain. Donnie’s body finally remembered the sequence: breathe slow, fall.
He didn’t crash. He didn’t lose. He didn’t even decide in a formal sense. Sleep came like the end of a sentence he hadn’t known how to finish, and Leo provided the period.
He was almost under when the last of his guard slipped sideways and a single affectionate phrase slipped out, quiet and slurred with exhaustion. “L’ve you...”
He woke enough to be horrified. He didn’t wake enough to walk it back.
Leo’s arms went tighter—not too tight. Safe-tight. “Love you too, genius.”
The next thing Donnie knew, the projector stars had drifted to a corner, the ambient music had looped, and Leo’s hand was still tracing slow circles on his cheek like he had all the time in the world.
Donnie slept upright, anchored and warm, and when he tipped, Leo tipped with him, a quiet correction barely bigger than a breath.
The lab would be there in the morning. The red in the schematic would wait. The humidifier (empathetic or not) could handle itself for one night.
Leo didn’t let go.
And Donnie, wired genius, professional insomniac, finally let himself sleep.