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There’s no scientific explanation for what’s happening to Donatello Hamato.
He’s a genius. A self-made technological prodigy. He operates with logic, with precision. Emotions, while acknowledged, are typically compartmentalized into manageable sectors of his brain.
But apparently, there is no compartment big enough for you.
You’re curled up in his hoodie, legs tucked underneath you on the lair couch, hair messy and glasses slightly crooked as you stare intently at the screen of your laptop. You’re reverse-engineering one of his drone’s command scripts. For fun. And maybe because he challenged you to, and you couldn’t resist.
Donnie is across the room, supposedly working on his battle shell. He’s holding a micro-soldering iron. But he hasn’t used it in thirty minutes. Because his eyes haven’t left you once.
You chew on your bottom lip when you concentrate. Do this little wiggle when your glasses slide down your nose, refusing to use your hands because you don’t want to break your work flow. You snark like it’s a superpower, but then turn around and give him the most genuine smile.
And that’s when it hits him.
He’s in love with you. Utterly. Completely.
The realization is instant. And horrifying.
Because you’re his best friend, his partner in crime. The one who yells at him to eat when he’s working too long and calls him out when he’s being ‘a smug, purple smartass.’ You’re also the one who listens to his rants, who understands his sarcasm. Who laughs at his dumbest puns and wears his hoodie like it belongs to you.
Still, somehow, he finds himself wanting more.
He wants to hold your hand when you’re hyper-focused. Wants to tuck your hair behind your ear when it falls in your face. Wants to kiss you after you sass him into a corner.
So naturally, he begins malfunctioning, dropping his soldering iron with a loud clatter.
You glance up, raising a brow. “You okay over there, D?”
He clears his throat, sitting up too straight. “Yes! Fine. I am functioning at optimal capacity, thank you very much.”
You squint at him, not convinced. “You sure?”
He tries to scoff, tries to pull off his signature aloofness. But his voice cracks halfway through and he ends up choking on air instead. You blink. And he wants the ground to open and swallow him whole.
This is mortifying, he thinks. A master of composure reduced to a sputtering mess by a simple question.
You set your laptop aside, concern softening your features. “Seriously, Don-Tron, you look like you’re about to short-circuit. Need some water? Or … a reboot?” Your attempt at a tech joke, one you know he usually appreciates with a dry chuckle, now makes his internal processors whir with panic.
He waves a dismissive hand. But it’s far too jerky, betraying his inner turmoil. “Negative! My … my processors are merely … recalibrating. Due to … atmospheric particulates!” He cringes internally. Atmospheric particulates? Really, Donatello? That’s the best your genius brain could concoct?!
You give him that look, the one that says you’re not buying it but will play along. For now. “Atmospheric particulates? In the sewer lair? Okay, Dr. Science.” The familiar nickname, usually a term of endearment, now feels like an accusation.
“Precisely!” he squeaks, then clears his throat again, trying to regain some semblance of dignity.
You rise slowly from the couch, still in his oversized hoodie, and Donnie swears time skips a frame. The hem swishes at your thighs as you pad barefoot across the lair towards him. “Alright, Doc. Let’s run diagnostics,” you say, tone playfully serious as you step into his space.
He stiffens. You’re standing too close. Not objectively close, but close enough that your shampoo tickles his sensory nodes.
“You don’t look optimal. You look like your neural network is spiking.” You tap his plastron with a single finger. “You overheating or something?”
“Preposterous,” he says, backing up, only to bump into the cluttered mobile workbench he was using. Casually, he tries to lean against it—only to knock over a container of screws. They spill everywhere.
“Uh-huh,” you murmur, folding your arms. “Definitely optimal.”
He wants to say something sharp. Something deflective. Maybe even something sarcastic. But then your face softens again, like it always does when you realize he’s not okay. And you do that thing where your hand rests gently on his forearm for grounding. For reassurance.
And his brain completely blue screens.
“You know you can talk to me, right?” you say, your voice quieter now. Not teasing. Not joking.
His vocal processors seem to have staged a mutiny. “Talk?” His voice shoots up three octaves, thin and reedy. “Regarding … what, exactly? The inevitable heat death of the universe? The latest advancements in neural network architecture? My … my perfectly standard, non-deviant, utterly nominal vocal output?” The last few words are practically a shriek.
You blink at him. Once. Twice. Then you slowly reach up and adjust your glasses. “I was gonna suggest talking about what you’re feeling,” you reply, tone dry. “But sure. Let’s start with the heat death of the universe and work our way backwards.”
If Donnie had a fan system, it would be blasting at maximum speed. Instead, he just stands there, frozen, trying desperately to reboot a single coherent thought. His brain is still trapped in a loop: She’s touching me, she’s touching me, she’s touching me—
“Unless …” You lean in slightly, just enough for him to notice the glimmer in your eyes, “the topic of feelings is causing that spike in temperature.”
He lets out a noise. Not a dignified one, but the auditory equivalent of a dying motherboard holding on for dear life. The sound escapes him before he can stop it, and your brows shoot up. He clamps a hand over his mouth.
There’s a beat of silence where you both just exist. You, with that slightly smug, knowing tilt to your head. And him, doing his best impression of a panic-stricken robot who just got hit with an unexpected firmware update.
Donnie’s hand remains glued to his mouth, eyes wide as if his own body has betrayed him on the most fundamental level. His other hand twitches at his side, like he’s running mental diagnostics but getting only error messages.
You place your hand over his. Gently pry his fingers away from his face. His eyes meet yours, still wide. Terrified. Then slowly—so slowly, as if buffering, he speaks, voice tight and squeaky around the edges. “That was … That wasn’t … I didn’t mean—”
Then, inevitably, the peanut gallery arrives.
Leo saunters into the room, stretching lazily. “Hey Donnie, have you seen my …” He stops short, taking in his brother’s rigid, almost statuesque posture and your amused yet concerned expression. His eyes narrow before that familiar glint of mischief appears in them. “I’m not interrupting anything, am I?”
“Leo, don’t you dare,” Donnie practically hisses, voice still several octaves too high. His gaze flicks between you and his blue-clad brother, a trapped animal assessing escape routes where none exist. “This is a … a highly sensitive recalibration process!”
Leo smirks. “Recalibration? Looked more like a full system crash from where I’m standing.” He looks at you. “What’d you do? Confess your admiration for his meticulously organized and alphabetized collection of bad guy threat assessments?”
You snort despite yourself, and Donnie lets out a strangled noise that’s one part gasp, another part groan, and three parts existential despair.
“Leo,” he says, tone lethal but wobbly, “do you have literally anything else you should be doing?”
“Not when you’re this entertaining,” Leo replies with all the smugness of someone who’s been waiting his entire life to catch Donnie mid-swoon. “Seriously, bro, I’ve never seen your face that flushed. Are you overheating or blushing?”
“I do not blush,” Donnie replies, his voice clipped and brittle, like it might snap in half under the weight of his own embarrassment.
You tilt your head. “I dunno, D. You are sort of radiating the same energy as a stressed-out Roomba caught in a corner.”
Leo cackles. “Ohh, that’s good. Can I use that?”
Donnie glares at both of you with the kind of energy typically reserved for malfunctioning lab equipment or Raph’s punching of things labeled FRAGILE. “I hate you both.”
“You love us,” Leo says. “But especially her, huh?” He throws you a wink and ducks just in time to avoid the screwdriver Donnie hurls in his direction.
After the tool clangs harmlessly off the wall, Donnie shouts, “Out!”
Leo exits stage left, laughter echoing through the lair.
Silence falls again. Except it’s not really silence—because Donnie’s heart is practically trying to punch its way out of his chest, and you’re biting your lip to keep from laughing too hard.
“Alphabetized villain assessments, huh?” you tease.
“It’s called preparedness.”
You poke his side, grinning as you tease, “But especially me, huh?”
His eyes meet yours. And this time, even through the flustered static still buzzing around his brain, he answers honestly. “I could never hate you.”
The next day, everything goes downhill.
Donnie spills oil on his blueprints. Walks into a wall. Nearly blows up his mini fusion cell because he accidentally enters your name instead of the energy input variable.
Leo, of course, catches his slip-ups instantly.
“Broo,” he drawls, dramatically leaning against Donnie’s workbench in his lab. “You’ve got it bad.”
Donnie stiffens. “I have no idea what you’re talking about.”
“Sure you don’t,” Leo says, twirling a stray wire between his fingers. “You only turned redder than a mutant tomato on prom night when she asked you to pass that tool thingy.”
Donnie scoffs. “That doesn’t even make sense. What mutant tomato? Prom night? Leo, your analogies are garbage.”
“Not as garbage as your poker face, lover boy.”
Mikey slides into the lab, grinning like a fox. “So when’s the wedding?”
“I-It’s not—!! I don’t—!!” Donnie sputters.
“Dude.” Even Raph joins in, chuckling. “Just tell her. We all know you like her.”
“I do not like her,” Donnie insists.
But then he thinks of the hoodie—his hoodie. You wearing it. The soft fabric, the way it hangs off your shoulders, the scent of you mixed with the faint, familiar smell of his own laundry detergent. The image flashes in his mind, clear and warm, and a traitorous little flutter happens somewhere in his chest cavity.
Threatening his self-control.
He covers his face with both hands. “Okay, I might like her.”
Raph raises an eyebrow. “Might?”
“Definitely,” Mikey says, voice sing-song. “You’re toast, dude. Emotional toast. And not the crunchy, golden-brown kind. More like the kind that fell butter-side-down into a pit of feelings.”
Donnie groans louder, dragging his hands down his face. “This is not how my cognitive trajectory was supposed to go today.”
“Then allow me to suggest a new trajectory.” Leo gestures grandly. “Operation: Tell Her Before You Spontaneously Combust.”
“Negative. Absolutely not. That’s a suicide mission.”
“Correction,” Raph says with a grin. “That’s a you’ve-got-a-chance-so-don’t-blow-it mission.”
Donnie bolts upright, pacing now. “You don’t understand. If I confess and she doesn’t feel the same, I lose everything.”
“She wears your hoodie,” Mikey says, as if this fact alone should end the discussion. “That’s like a universal sign of mutual crushing.”
“Correlation is not causation,” Donnie mutters, then spins around with wide, panicked eyes. “And what if she’s just being … nice? What if she just thinks of me as—”
“Don’t say ‘brother,’” Raph interrupts with a grimace.
Mikey throws an arm around Donnie’s shoulders. “She reverse-engineered your drone code for fun. If that’s not love, I don’t know what is.”
“Donnie.” Leo crosses his arms. “You’re stalling. Again.”
“I require more data before making a declaration.”
Leo smirks. “Or you could just ask her how she feels.”
“Statistically, that has a high margin of—”
“Just talk to her,” Raph says. “Before your nervous system explodes.”
Later that night, you’re snuggled back in Donnie’s hoodie. It still smells faintly of him. Something uniquely, comfortingly him.
You’re on the same spot on the couch, scrolling through lines of code. It’s Donnie’s latest security encryption. It’s unnecessarily complex, almost ridiculously so, like he wanted to see if you’d lose patience with it.
You haven’t. And if anything, you’re more determined than ever to crack it.
Donnie stands just inside the lab entrance, fingers twitching at his sides, almost like he’s mentally rehearsing lines. He watches you, a soft, almost bewildered expression on his face. For once, he doesn’t even try to analyze the storm of variables churning within him. He just feels it. All of it.
He clears his throat, the sound a little too loud in the quiet lair. He walks over, hands clasped tightly behind his back, his usual confident stride replaced with something a little more careful. Like he’s approaching a very delicate, potentially explosive experiment.
You glance up, a warm, welcoming smile spreading across your face. “Hey, D.”
He sits down beside you, perhaps a little closer than strictly necessary, but still maintaining a careful distance. You can feel the slight warmth radiating from him. You wait, watching him with an encouraging gaze.
“I …” he starts, then stops. His brow furrows. He swallows, eyes darting away for a nanosecond before refocusing on some indeterminate point near your shoulder.
“You okay?” you prompt gently.
A faint flush of pink dusts his cheeks. “No atmospheric particulates this time,” he mumbles, the words barely audible.
You smile wider, your heart doing a little flutter. “That’s a relief.”
Then he says it, his voice dropping to barely a whisper, gaze fixed firmly on his now-trembling hands in his lap.
“I like you.” His hands twitch, fingers interlacing and unlacing. “Like. More-than-best-friend like. Not just ‘you-stole-my-hoodie’ like—though, for the record, that is also a contributing factor. I mean. You can still steal my hoodie. In fact, I … I hope you do. Often. Preferably forever.” He finally risks a tiny, hopeful glance at you.
A soft chuckle escapes you. “Donnie, is this your version of flirting?” you ask, your tone gentle, your own cheeks feeling a little warm.
“I … I genuinely don’t know,” he admits, looking utterly lost, his shoulders slumping a fraction. “I think I’m glitching.” He looks so earnest, so vulnerable, that your heart melts.
You lean forward, your smile softening into something tender. You reach out, slowly, giving him time to pull away if he wants. He doesn’t. You cup his cheek with your hand, your thumb gently stroking his skin. He leans into your touch. Eyes wide, a tiny, almost inaudible sigh escaping him.
“Well. For the record?” you say, and he holds his breath, his gaze locked on yours. “I like you too, Donnie. Like, ‘please keep giving me impossible tech puzzles so I have an excuse to spend ridiculous amounts of time with you because you’re brilliant and funny and sweet.’”
He blinks a few times before his systems finally restart. A slow smile spreads across his face, lighting up his features. To you, it’s like watching a sunrise. “You … do?” The disbelief in his voice is almost painful, but it’s quickly being overridden by dawning joy as he digests your words.
“I’ve been waiting for you to catch up, genius,” you tease, your thumb brushing along the line of his jaw. “Took you long enough. I was starting to think I’d have to spell it out in binary.”
He exhales a short, shaky laugh. Part shock, part awe, all relief. “My predictive algorithms … they … I was running every probable outcome. This one … this one had a statistically lower probability than I preferred, given the stakes.” He shakes his head, still smiling that dazzling, rare smile.
“And which one did your brilliant brain finally land on?” you murmur, your faces incredibly close now—so close you can see the way the light catches the unique patterns in his irises.
He leans in, his gaze dropping to your lips for a breath before meeting your eyes again, his voice a soft, warm whisper against your skin. “This one.”
Then he kisses you.
It’s hesitant at first, a gentle press of lips. Careful, like an experiment he wants to get perfect. You can feel the slight tremor in his hands as one comes up to rest on your waist, the other still on the couch, gripping the cushion. You sigh into the kiss, your own hand moving from his cheek to tangle lightly in the ends of his mask tails, encouraging him.
He deepens the kiss slightly, a spark of newfound confidence igniting. It’s sweet, and a little clumsy, and utterly, breathtakingly perfect.
And for once, Donatello Hamato doesn’t need data, or algorithms, or any empirical evidence to know that this feeling—this connection—is his best, most wonderful result yet.