This story is a slow-burn, emotional poly romance centered on the Bayverse TMNT. I’m writing it just for myself, but if you’re here for emotionally layered storytelling, hurt/comfort, complicated feelings, and protective turtles… welcome.
Reader is a human woman with a blend of seriousness and dry humor. Romance develops slowly and organically. NSFW content will be included in later chapters and tagged accordingly.
I do not own TMNT or any related characters—this is a non-profit fanfiction written for personal enjoyment.
Chapter 1: Crashing into the Shadows
You knew the moment the ground gave out beneath you that something was wrong.
There hadn’t even been time to scream—just the sudden, weightless drop, the crack of wood and metal, and then a cold, wet impact that knocked the air out of your lungs. When the pain hit, it was sharp and immediate, radiating from your left leg. You didn’t know if it was broken, but it hurt like hell.
You’d landed somewhere deep—too deep. Your phone screen had shattered on impact, the flashlight cracked but still flickering in your grip. Concrete and rust surrounded you in every direction. The tunnel stretched on, damp and echoing. No ladder. No exit signs. Just a passage, one you hoped might lead somewhere up.
You walked. Limping. Breathing hard. Every now and then, water dripped from overhead, the splash loud in the silence. You tried not to think about rats.
Eventually, you found a hatch. Heavy, metal, built into the ceiling like some kind of industrial maintenance point. You hesitated, then reached up, bracing yourself as you pushed.
It gave with a groan.
You climbed slowly, carefully, pain biting into your leg as you forced your body to cooperate.
And when you emerged, you froze.
The space above wasn’t another tunnel or abandoned room—it was lived in. Concrete walls. Neon lights. Old furniture. A massive TV, shelves stacked with books and wires, a punching bag hanging from a steel beam.
You didn’t have time to process much more.
Something massive moved in your peripheral vision.
You turned, pulse spiking.
And then—he was there.
A figure stepped into view, casting a heavy shadow in the dim light. Broad shoulders. Arms like tree trunks. Skin green. A shell. A face you couldn’t begin to comprehend—part reptile, part man, all wrong.
You stumbled back.
He moved toward you, fast.
“Who the hell are you?” His voice was rough, low, edged with something dangerous.
You couldn’t speak at first. Your breath caught in your throat.
He stepped closer, looming.
“You deaf?” he snapped.
“I—I didn’t mean to come here,” you managed. “I fell. I was trying to find my way out.”
He didn’t lower his guard. “Bullshit.”
“I’m not lying,” you said, voice steady despite the cold settling into your limbs. “I fell through a construction site. The street gave out. I didn’t even know this place existed.”
A second shape moved behind him. Then a third. You backed up, breathing faster.
This one was was wearing a blue mask. He held himself differently: spine straight, movements smooth, calculating. His eyes locked on you like he was assessing every variable at once.
The third moved with sharp precision, his expression unreadable, hands subtly adjusting something on his wrist. His glasses caught the light.
“I told you we should’ve reinforced that access tunnel,” the one in the blue mask murmured. “Now we’ve got a civilian in our living room.”
“She could be a scout,” the first one said. “A plant.”
“For who?” the one with the tech asked. “No one topside knows how to get this deep without help.”
“I didn’t come looking for anything,” you cut in. “I didn’t even know this was here.”
“Convenient,” the first said, voice cold.
“She’s bleeding,” the blu masked one interrupted, his eyes scanning your leg. “Fall wasn’t shallow.”
“I’m fine.”
“You’re not,” he said. “And that wound’s already turning.”
You swallowed.
The one with the tech stepped forward and crouched near you, not touching, but inspecting. “Laceration along the outer calf. Maybe seven inches. Not deep, but you’re right on the edge of infection risk.”
“I can walk.”
“Not for long,” he replied simply.
The tension in the room hadn’t broken. The one closest to you—the one who’d confronted you first—still watched with suspicion, shoulders tight, fists clenched. The leader—the one who’d spoken first from behind—studied you with a soldier’s eye.
“Raph, back off,” he said quietly. “Let Donnie take a look.”
So the tall one was Donnie. The one with the authority in his voice must be Leo.
And the first—the one still glaring—Raph.
You didn’t speak as Donatello carefully helped you down from the edge of the hatch. His hands were steady. Surprisingly gentle. There was a stiffness to him, not unkind, but clinical. Detached.
“I need to clean it,” he said.
You sat on the edge of an old bench, watching the way he moved—precise, calm, like every action was part of a system only he understood.
Raph paced behind him, never letting you out of his sight. Leo stood still, arms crossed, watching you just as closely.
You sat quietly through the treatment. No jokes. No bargaining. Just the sound of water and antiseptic, the burn of gauze against open skin, and the weight of three unknown lives pressing down around you.
When it was done, Donnie stepped back.
“You’ll be okay. But you need rest.”
“I don’t want to stay here.”
“We’re not giving you a choice,” Raph said sharply.
Leo didn’t correct him.
“You’ve seen us,” Leo said. “We don’t know you. That’s a risk.”
“I didn’t ask to see anything,” you replied, keeping your tone even. “I didn’t come looking for trouble.”
“That doesn’t change what’s already happened.”
There was silence for a moment. Donatello’s gaze flicked to Leo, then to you.
“You’re not the first person to end up in the wrong place,” Donnie said, quieter than the others. “But you are the first to survive the fall and see this much.”
“So what happens now?”
Leo’s expression remained unreadable. “You stay. For now.”
You swallowed, jaw tight. You didn’t want to argue, not when you were outnumbered, injured, and deep underground. But you didn’t want to be held captive either.
“Not a prisoner,” Donnie clarified, as if sensing your thoughts. “Just…contained. Until we can decide what to do.”
⸻
Later, they let you lie down on an old couch tucked in the corner of the space. Your leg throbbed, and you couldn’t quite shake the feeling of being watched.
When you woke—still exhausted, disoriented—there was a blanket pulled over you. A bottle of water beside your arm. And a note scribbled on the back of what looked like a torn blueprint.
You’re not trusted. Don’t make that worse. Stay put. — R
You stared at it for a long time.
Then you sat back, silent.
This was real. And you were nowhere near the surface anymore.
I genuinely believe that April in 2012 could have been an amazing character and her and Donnie could have been so cute together if she wasn’t written so poorly. In saying that….
I want Raph to get angry at her. I really want there to be a moment where April has just led Donnie on yet again, giving him another cheek kiss then just a day later telling him to leave her alone and going out on a totally not-a date with Casey. Raph is the only one who sees the tear brimming in his little brothers eyes and he’s had enough, no one hurts his brothers, especially not like that.
April has just left the lair and Raph follows her, waiting until she turns around to ask whose there to bring his Sai up to her throat while shoving her against the wall.
She protest, a brief look of fear in her eyes before she clearly gets annoyed, “Raph, what the hell are yo-“
“shut it. You’re going to listen to be because you only get one chance and I ain’t repeating myself. My brother is an idiot, he’s a mad genius but he’s still a person and he loves you. I don’t give a shit if you don’t love him back, you don’t have to, but if you play him one more time for whatever pathetic reason you have, wether it’s you want attention or your just a soulless freak, I will kill you. It won’t be quick, it won’t be painless, and they’ll never find you to give your dad solace. My brother deserve better than anything you could give him, so either accept him as he is, mutant and nerd and all, or back the fuck off. Got it?”
April is shaking by that point, a small cut already appearing on the front of her neck as well as a smaller one on the side where the smaller prong of his weapon digs in. She looks close to crying but she’s still a brave person and keeps it.
She nods rapidly.
Raph leaves, letting her slump to the floor while gasping for breath and he doesn’t look back. They ask what happened to her neck the next day and she says nothing, though Mikey notices her being tense around Raph who looks eerily calm.
The room around you—dimly lit and oddly quiet—was still foreign. Too quiet. Every creak of metal, every low hum of machinery in the walls kept you on edge. You’d tried shifting under the blanket they left, but the dull ache in your calf reminded you you weren’t going anywhere soon.
It wasn’t until hours later that you heard voices.
Low at first, then rising slightly—enough to make out distinct tones. You stayed still, listening. Three of them again.
“She’s not a threat.” That was Donatello. Calm. Measured.
“You can’t be sure,” Leo said. His voice carried authority, but not cruelty. “This could’ve been a setup. Someone could have known about us.”
“No one aboveground has that kind of intel,” Donnie replied. “And if they did, they wouldn’t send one unarmed civilian limping through a tunnel.”
A pause. Then the unmistakable growl of Raph: “I still don’t like it.”
“Yeah?” Donnie answered. “You don’t like anything.”
You almost smiled at that. Almost.
But then the hatch creaked again. New footsteps this time—lighter. A different energy entirely.
“Guys, why didn’t anyone tell me we had company?!” The voice was younger, lighter, undeniably curious. “You’re telling me I missed a whole human falling into our house? That’s, like, a top ten sewer event.”
You sat up slowly as the footsteps approached.
He was the shortest of the four. Still big—bigger than any human you’d ever met—but slighter than his brothers. Orange mask. Blue eyes that flicked toward you with no fear at all. Just open curiosity.
“Hey,” he greeted with a wide grin. “You awake?”
You nodded once.
He walked closer, careful not to crowd you. “Name’s Michelangelo. But you can call me Mikey. Everyone does.”
You didn’t answer immediately. He waited, patiently, then added, “You don’t have to talk if you don’t want. I get it. I mean, weird day for you, huh?”
“Yeah,” you said quietly. “Something like that.”
Mikey crouched beside the couch, arms resting on his knees. “You’re not hurt bad, right? Donnie’s got, like, ninety-eight first aid certifications. I think he invented half of them.”
“She’s healing,” came Donnie’s voice from across the room. He’d entered without you noticing. “But slowly. I don’t want her moving around too much for at least another day.”
You glanced at him. Tall. Quietly intense. He hadn’t looked at you directly since entering—but you knew he was watching. He always was.
“I won’t go anywhere,” you said. “I don’t even know where I am.”
Leo stepped into view then, eyes sharp. Blue mask. Broad shoulders. The kind of posture that told you he was always waiting for something to go wrong.
“You’re in our home,” he said. “And we’re still deciding what that means.”
You met his gaze, refusing to flinch. “I didn’t ask to be here.”
“No. But you are.”
“I told you the truth.”
“And we heard it,” he said. “But truth isn’t always safe.”
“Leo,” Donnie said quietly.
Leo exhaled through his nose, then finally nodded. “You’re not confined. But you don’t leave this room without one of us nearby. Not yet.”
You nodded back. That seemed fair—considering.
Mikey clapped his hands once. “Cool, now that the prison terms are outta the way, can we feed her? I mean, I don’t think we’re monsters, right?”
“I’m not hungry,” you said, automatically.
“You will be,” Donnie murmured as he walked past, already moving toward a panel built into the wall. You noticed how his eyes flicked toward your leg again before he disappeared into a side hall.
Mikey grinned and stood. “I’ll heat up something. You ever had sewer-baked mac and cheese? It’s mostly edible. Sometimes even cheesy.”
You blinked at him.
He grinned wider. “Kidding. We have real food. Promise.”
⸻
A few hours later, you were sitting on the edge of the same couch, a reheated slice of pizza balanced on a plate beside you. Your leg still throbbed, but the pain was manageable. You couldn’t say the same about the tension in your chest.
The room was quieter now. Raph sat in the far corner, leaning against the wall with his arms crossed. Hazel eyes shadowed. Watching. Not talking.
You could feel his distrust like a physical weight. He didn’t bother hiding it.
“You got a name?” he asked suddenly.
You glanced over. “Yeah.”
He raised a brow. “Gonna share it, or are we supposed to keep callin’ you ‘the human’?”
You gave it.
Raph grunted. “Hmph.”
That was the end of the conversation.
You sat in silence, unsure what to do with yourself.
Then Donatello reappeared. He didn’t speak at first, just pulled over a small terminal, tapping quietly. The glow of his tech cast faint shadows on his face, softening the angles.
“I rerouted the security feed,” he said without looking up. “No one’s followed you. No unusual movement topside.”
“Thanks.”
“I didn’t do it for you,” he said. But his voice wasn’t cold. Just distant.
Leo returned last, his gait quiet, posture still rigid. When he entered, the energy in the room shifted. Like everyone braced just a little.
“We’ll take turns watching,” he said to his brothers. “One of us is always in the room while she’s here. At least until we’re sure.”
You looked down at the floor, jaw clenched. “You think I’m a threat.”
“I think you’re a variable,” Leo said. “And we don’t leave variables unchecked.”
“You don’t know me.”
“No,” he said. “We don’t.”
⸻
Night fell, if it could even be called that underground. The lights dimmed on a cycle—less a sunset and more of a power-saving mode. You curled back up on the couch, eyes heavy. Your leg ached. The silence pressed down again.
But there were sounds, soft ones: the hum of Donnie’s tech, Raph’s breathing from across the room, the faint rhythm of Leo’s footsteps pacing.
Mikey had fallen asleep on the floor nearby, curled on a blanket like a cat. You didn’t know what to make of him yet—too open, too light—but he was the only one who hadn’t looked at you like you were a problem waiting to explode.
You turned your head slightly.
Donnie was still at his terminal. Eyes focused. Fingers moving. But every few minutes, he glanced over—just for a second.
You woke in the early hours—if they could even be called that, underground.
The air was colder, the lights dimmed to a soft glow. Your body ached, the makeshift couch no match for real comfort, but that wasn’t what kept you awake.
It was the stillness.
The quiet kind of still that feels wrong, like the world has paused just long enough for your thoughts to catch up—and drag you under.
You sat up slowly, adjusting your leg, careful not to shift the fresh bandages. The pain had dulled, but it was still there. A lingering reminder that you were somewhere you didn’t belong.
You glanced around.
Mikey was snoring softly on a floor cushion, limbs sprawled out like he’d collapsed mid-story. Raph wasn’t in the room. Leo stood near the far wall, arms crossed, eyes closed—not asleep, just resting. Watching without looking.
And Donatello was where you’d last seen him—seated at his workstation, tall frame hunched slightly forward, light from the interface casting a pale green glow on his face.
You stared for a while before deciding you couldn’t sit there anymore.
Pushing yourself to your feet, you limped quietly toward him, biting down on the discomfort. He didn’t turn until you were within arm’s reach.
“You should be off that leg,” he said, without looking up.
“I know.”
“You need something?”
You hesitated, then slowly lowered yourself to sit against the nearby wall. The metal was cold, the floor unforgiving—but it grounded you.
“No,” you said finally. “I just… didn’t want to be over there anymore.”
He still didn’t face you fully, but his posture shifted—less guarded now. “Can’t sleep?”
You nodded. “Too quiet.”
Another pause.
“You get used to it.”
“Do you?”
He looked at you then. His green eyes were striking in the low light—sharp, but not unkind.
“Eventually,” he said. “Or you stop noticing.”
That made you go still.
You watched him for a moment, the silence stretching between you. The hum of tech filled the gap.
Then you exhaled, quiet and slow. “Can I ask you something?”
He nodded once.
“Why didn’t you question me? The others… I get it. I’m a stranger. I know that. But you treated me like I was already part of something.”
Donnie’s expression didn’t change. But you saw his hands still. The faintest flicker of thought behind his eyes.
“Because I listen more than I assume,” he said simply.
You looked away. That landed harder than you expected.
After a moment, you whispered, “I don’t have anyone.”
Donnie didn’t speak. But you felt him shift again—like a frequency tuning in, quiet and steady.
“My family’s gone,” you said. “Not recently. But… it doesn’t go away. The feeling. You move forward, but you’re still carrying the weight. And I moved here thinking I could rebuild something. Start over.”
The words scraped out of you like gravel. You hadn’t meant to say all of it. But it was too quiet not to speak.
“I haven’t made any real friends yet. I keep telling myself it just takes time, but sometimes I think… maybe people just stop trying after a while. Maybe I did.”
You looked down at your hands. “And now I’m here. In a place I shouldn’t be. With people who probably wish I wasn’t.”
Donnie was quiet for a long moment. Then he leaned back slightly in his chair, adjusting the screen so the light wasn’t shining in your face.
“No one asked to be down here,” he said softly. “We didn’t choose this life. We were forced into it. And we’ve made the best of it—but trust me, there are days where even the best feels like survival.”
You blinked.
He wasn’t looking at you anymore—just the space in front of him, somewhere far away.
“But the ones who find us—accident or not—are always the ones who were looking for something. Even if they didn’t know it.”
You swallowed. Your throat was dry.
“What makes you think I was looking for anything?”
Donnie gave the faintest smile. “Because you stayed awake. And you walked toward me instead of away.”
You didn’t answer. You didn’t have to.
The silence that followed didn’t feel heavy anymore. Just real.
Then Donatello stood slowly, turning off the interface screen. He moved to a tall storage cabinet, pulled something out, and returned with a blanket—heavier than the one you’d had before. Thicker. Cleaner.
He handed it to you without a word.
You took it carefully.
“Try again,” he said. “Sleep’s easier when you’re warm.”
“Donnie,” you said quietly.
He paused.
“Thank you.”
His eyes met yours again—green, steady, and for the first time… soft.
“Don’t thank me yet,” he said. “I’m still not sure I trust you.”
“But you’re the only one who doesn’t treat me like I’m a threat.”
He didn’t smile. But something in his expression eased.
“Maybe that’s why I’m the one who should be careful.”
And with that, he walked back to his workstation—shoulders relaxed, attention shifting—but not before glancing back once more.
Raph had rough houses with humans before, outside of training and play fights with his sister. He’d dealt with bank robbers, a guy who tried to steal a cat, basic thugs, all kinds of people.
Yet he never killed any. That was too far.
But then they went out with their Yokai made human disguises, which they couldn’t control outside of changing clothes and the like, and two men decided to mess with his brother. Leo was wearing a gorgeous, blue knitted sweater with yellow flowers, a small white crop top and a pair of ripped up jeans, some white heeled boots that gave him a few inches to finish it off. His bold, red eyeliner and lipstick, black mascara and soft pink blush had taken him only ten minutes, years of practice helping him get it done in no time. Yet despite how beautiful his brother look (and Raph would spend the rest of his life making sure it was known he had the most beautiful brother in the world), some people seemed to have an issue with it.
The looks they were used to, Raph and Donnie easily scaring anyone off before they could do any harm aside from making their brother insecure. But these two men in particular chose to shoved his brother, pushing him against the wall and causing him to twist his ankle badly. Leo was left in shock, unable to call on instinct to help himself as the two men started shouting slurs and abuse at him.
If it hadn’t been night, maybe Raph would of been able to reason with his own rage a little more, alas it wasn’t.
He had ordered Leo to open a portal, who did without question though a bit of shaking, allowing Raph to grab both men and drag them through. Leo hadn’t joined him, going home to sob into his twins arms, but they all knew when Raph came home with bloodied hands and news reports spoke of two missing men that Raph had dealt with them in his own way.
No one ever spoke about it, not even when it happened again and Leo told Raph to just go home, that he could handle it this time. Raph didn’t regret his choice, not when Donnie and Mikey gave him looks to say they wanted to do the same thing.