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It had started with the pillows, Mikey had been in gremlin mode all day, skipping around the lair with a king’s authority.
Casey had been too tired to argue. Dumbass had dragged every soft object from every corner of the lair into a lopsided heap on the floor. Couch cushions, body pillows, rolled-up blankets. The thing looked like a nest. Like something built by someone who’d never seen a bird in his life but figured “soft equals safe.”
Casey might’ve laughed. Might’ve snapped a pic, teased Mikey later but he was warned not to do that by Leo. Leo being freakishly anal as always. Mr,Stick In His Ass.
Once night fell and the lair went quiet, Casey realized that Mikey had really built a strange sanctuary for himself and his family. Subconsciously.
A pile of scavenged softness four feet high in the back corner of the living room, lit only by the flicker of the TV’s standby light. Blankets hung over the pipes above like a makeshift canopy.
He couldn’t stop staring.
Not at the lovely nest Mikey created mind you, but who exactly he saw curled in the left side of the pallet.
Raphael—THE Raph, who slept with a sai under his pillow and once punched through a wall because April startled him awake— had his older brother’s arms around him like a shield, one hand flat against the curve of his shell. Raph was half on top of Leo, one leg tossed carelessly between Leo’s thighs, head pressed into the crook of Leo’s neck like belonged there.
They were breathing together, Slow. Measured. In sync. No space between them—no boundaries. Just heat, tension, and something desperate layered under the surface.
He knew what it looked like when someone needed another person. He knew what it looked like when someone claimed another human being for themselves.
That’s what this was. Claiming.
They both had deep and ugly bruises nearly everywhere. Fading, but visible. Leo’s bandana had slipped sideways, leaving most of his face exposed. Raphael had a cut on his lip, as if he’d bit it down hard enough to bleed.
Casey wanted to take another step forward from the kitchen, but it felt like trespassing. He was walking in on something he had no right to see, something private and raw that didn’t belong to anyone but the two of them. This wasn’t his business. He knew that but something in him twisted. Not jealousy, but a sick hollow sort of grief because once, not that long ago, Raphael had been his best friend.
The kind of friend who stayed up all night having deep conversations that hovered close to real feelings., who grunted instead of saying thank you, who picked fights just to mess with you. He remembered Raph crashing at his place when things got tense in the lair. Remembered pizza nights, rooftop fights, shit talk. He used to matter to Raph.
Now?
His best friend barely spoke to him. Missed calls, ignored texts. Yet here he is sleeping on top of Leo like they’d been happily together for years. As if they never butted heads or beat the shit out of each other when arguments were getting to far.
His ‘best friend’ made a soft sound in his sleep—almost an animalistic whimper—and Leo responded by tightening his arms around him, the sound afterwards coming from the snapping turtle sounded like a purr.
Raph could purr? Since when.. Casey’s throat is now dry. He never hear Raph do that around him..
He knew trauma. Knew what it did to people. He wasn’t naïve enough to think this was about sex—though God, the way Leo’s fingers curled around Raph’s thigh made it damn hard to ignore that possibility—
Casey clenched his fists. How did he not notice this? Raphael is his best friend! Has it always been there? Hiding under the surface? He felt a small wave of betrayal.
Casey didn’t hear Donnie at first,, He stared too long. How the hell was he supposed to unsee this? To busy in his thoughts.
“Careful, Your brain might melt if you think long enough.” Donnie stood just a few feet away, holding a mug and watching Casey with an expression that wasn’t quite surprise and wasn’t quite indifference either.
“They’re brothers, Don.”
“They’re trauma-bonded,” Donnie corrected softly.
“That moral line got blurry a long time ago.”
“That’s… not an excuse!”
“No,” Donnie agreed. “It’s just a warning.”
“That’s bullshit.” Casey’s voice spiked before he caught himself. “I mean—look at them!
“I do,” Donnie said. “I have too every single day. I don’t have a choice.”
“They’re…” Casey struggled, eyes narrowing. “That’s not normal.”
Don rolled his eyes. “And what about any of us is?”
Casey’s fists tightened at his sides. “They’re BROTHERS, Don.”
“They were,” Donnie said evenly. “Now they’re something else.”
“So.. You’re not gonna fucking say anything?” Casey asked, keeping his voice low. He looked down at his feet, heart pounding.
Donnie followed his gaze toward the pile of turtles tangled in the corner. He took a sip of coffee. “What exactly do you want me to say?”
“Ohh I dunno. Say it’s not weird? Tell me I’m overreacting? Since you’re SO supportive!”
“You’re not,” Donnie said flatly. “It’s weird.”
Casey turned to him, desperate for some kind of shared ground. “Then why aren’t you freaking out? ! The hell???”
“I know what it’s like to watch someone fall apart and what it looks like when they cling to the only person who understands.”
“That’s not—” Casey paused, shaking his head. “Raph’s not like that. He doesn’t do clingy.”
“Not with you.” This wasn’t said unkindly but landed like a punch.
“…They’re brothers,” Casey said, like repeating it to himself made that last sentence disappear. “But this—” Casey gestured vaguely toward the nest. “They’re touching like they— I knew Raph is intense who emotions or whatever, but…” Casey shook his head. “I didn’t think he’d ever—they’d ever— I used to be his best friend,”
Donnie looked at him confused. “You still are?”
“Doesn’t feel like it,” he said. “I didn’t even know.. I missed the part where everything changed and now I’m just… standing outside of it. He didn’t even tell me.”
“Raph’s not yours to fix anymore and if you try to pull them apart, they will break you then crawl back to each other anyway. He probably didn’t tell you because of your reaction right now.” The turtle whispered the last sentence— “It’s far too late now.”
“I.. didn’t think he’d pick Leo over me,” Casey admitted. His voice cracked on the last word. Donnie looked at him for a long moment. Not pitying—just quiet.
“He didn’t, He just stopped needing you the way your used too.” That hurt even more.. so Raph liked him that way? His chest hurts.
Casey looked back at them. “It’s not supposed to be like this.”
“No, it’s not, but here we are.”
“What are they even doing?” he asked, softer this time. “I mean, what is this?”
“You know exactly what it is.”
“You’re saying they’ve been—” Casey swallowed hard.
Donnie gave him a look. “You think I don’t know what sex looks like?”
Casey clenched his fists. “That doesn’t mean—!! … have they..?” Casey paused. He hated the question forming in his throat.
Donnie spared him. “Does it really matter?”
“Yeah, it kinda does smartass!”
Donnie didn’t flinch. “That's not the root of the problem. It’s just a symptom. Sleeping, yes. Together? Obviously. In the sexual sense? Very likely.”
Casey’s eyes widened staring at the taller mutant.
“I don’t think they understand how serious this has become between them. It’s quite an interesting subject to study, really.”
Don is now going on a passionate tangent. As if his incestous brothers were a long college essay paper. An experiment for his own research. Don spoke like he was reading from a chart— this was just data.
“Why are you talking about them like test subjects?!”
“It’s how I cope with the situation,”
Casey barked a bitter laugh. “So what, you’re psychoanalyzing incest now?”
“Not moralizing. You can try to frame it in black and white if it makes you feel better, but that’s not the world we live in. They’re probably addicted to each other by now.”
“They stopped sleeping in their own rooms two months ago.” Casey’s breath caught. Donnie took another sip of bitter coffee, like he was discussing the weather. “They think they’re subtle. They’re not.”
Casey’s jaw clenched. “That’s not—Raph..he’s not like that.”
“No, He’s far worse. I’m actually being very lenient given your circumstances right now.”
“You’re just OKAY with that?!” Casey shook his head like he could rattle the images loose. “This is—this is so wrong.”
Donatello rolled his eyes “Morally? Biologically? Psychologically? Be specific.”
“All of it,” Casey snapped.
Donnie leaned his hip against the counter, gazing past Casey with a detached sort of sorrow. “Then you haven’t been paying attention.”
Casey’s eyes darted back to the two sleeping forms. Leo had shifted again, his hand moving farther up Raphael’s thigh. fingers brushing under his shell like he belonged there. As if he was allowed to touch places no one else dared to look at..
Casey’s chest tightened. “They used to hate each other half the time. Now they’re—what? Sleeping together?” Casey’s voice cracked, now he felt guilty for pinning his frustration on Donatello. “…Why didn’t you say anything?”
“To who Casey? Splinter’s gone. April’s avoiding the lair going to college. Mikey already knows. You wouldn’t have believed me anyway.” Don looked annoyed by how long this conversation is going..
And Casey—
He didn’t know what to say to that.
Donnie signed looking down into his mug. “..They got weird after Leo’s coma. Raph wouldn’t leave his side. At first I thought it was just trauma, maybe Guilt. Hypervigilance, but then it didn’t stop. It got worse over time.”
Casey frowned.
Donnie nodded. “It started that way but now it’s grown into something else.”
“Is.. it love?” Casey asked, quieter now.
“Personally, I think that’s the problem.”
Silence again. Heavy. It felt wrong to watch. Wrong to know. All of it, wrong.
He just knew that something about all this made his skin crawl, this was a kind of intimacy he didn’t understand. “They used to fight all the time,” he said suddenly. “I used to be the only one who could calm Raph down. He’d call me to blow off steam. Punch walls. Talk shit.”
Donnie nodded. “He still trusts you, just not the way he trusts Leo.”
“That wasn’t always the case!.. right?”
“No, but Leo almost died and Raph was the one he wanted. I’m guessing the two of them said ‘fuck it’ and talked to each other about everything.”
Casey ran a hand down his face. “I feel like.. I lost him.”
Donnie was quiet.. Then, finally, “You did.” It was said without any judgment. Casey swallowed hard trying not to cry. “but, you still have him in a different way.”
Casey stepped back, breath shallow. The Raph he knew liked him romantically but now Leo has taken that spot.. Raphael has been treating him as any friend would. Platonically. “Do you think.. they even see what this is turning into?”
Donnie looked at him—really looked—and his expression was unreadable. Cold, but not unkind.
“I think they don’t care,” Donnie said. “And if you try to pry them apart, you’ll make it a lot worse.”
“So I’m supposed to just… silently accept it?”
“No. You’re supposed to decide if your friendship with Raphael matters more than your discomfort.”
That landed like a gut-punch.
“So.. what do I do now?”
“You either let him go or stay. It’s your choice.”
Casey looked at them one more time; Just long enough to accept that whatever had bloomed between them—obsession, love, trauma, need—it wasn’t going anywhere.
And neither of them would let it.