He's sitting in the dojo, eyes closed. Splinter's warmth is at his side, a solid, reassuring presence, steady breathing in time with Leo's own heart. Outside the walls he can see his brothers talking and laughing; not a distraction, but a comfort, a reminder that they are here and safe.
Leo closes his eyes, breathes deep...
"My son?"
He opens his eyes, frowning. "Yes, Sensei?" His father is staring at him with an unmistakable look of worry. "Is everything all right?"
Splinter just shakes his head. The gesture makes Leo's breath catch; has he done something wrong?
"My son..." Splinter reaches out, resting his hand on Leo's shoulder. "I-- Leonardo..." He shakes his head. "I am so sorry, my son."
Leo opens his mouth, only to be abruptly yanked into a tight, desperate hug. "So sorry," his father rasps. 
"Father?" He reaches up, clutching awkwardly at his Sensei's arms. "What's going on?"
"You must remember us," Splinter whispers. "Us, as we truly are. You must come back home." He lets out a soft sob.
"I am home, what do you--"
His father's grip tightens, cutting him off. "We are waiting for you," he whispers, voice trembling. "And all you need to do is come back to us."
His grip tightens, tightens. Tightens, and Leo is gasping, trying to remember if the arms holding him were always so big.
"Simple enough," and Sensei's voice is changing, growing deep and gravelly, "For someone who isn't a faithless, backstabbing, loose little whore." His hands tighten and Leo cries out as he's thrown, shell hitting the floor with a sharp clack. 
"Fa--" But the words die in his throat as he looks up to see a massive rat pinning him down to the ground, growling through twisted yellow teeth. It shrugs off the last of its tattered robe, revealing filthy, blood-coated fur and a throbbing cock.
"No!" Leo shrieks, trying to twist away. His head turns and that's when he sees the bodies piled up on the floor besides him. Burnt and stinking, but he'd still know them anywhere. Mikey's fingers, shriveled down to blackened twigs, are still lifted in a final goodbye.
The rat laughs, low and deep. "Pretty sight, aren't they?"
"Murderer," Leo sobs out, bucking and yanking to no avail.
"I wouldn't have to do it if they hadn't been so useless," the rat spits, yanking Leo's legs apart and dragging his tail down. "If you had done a better job of leading them." He shoves inside, breaking Leo's world into screaming, white-hot pain. He shrieks.
"Take it," the rat groans, eyes rolling with pleasure as he spears Leo with sharp, vicious thrusts. At the corner of his eyes Leo can see his brothers creaking into upright positions, maggots spilling from their mouths like drool. "Just take it, you fucking slut."
"Help me," Leo sobs as his brothers totter towards him. "Please..." Mikey waves at him, rotting teeth twitching into an idiot grin. And then he sees that they've all got their cocks out, that they're touching themselves with vengeful smirks on their faces.
"No!" He's screaming now, in pain and terror and helpless rage. "No no no no!" The rat just laughs at him, filling Leo's face with the scent of rotten meat.
And he's still screaming when his eyes snap open. There are hands on him and he's crying out, batting them away--
"Leonardo. Leonardo!"
Strong, muscled arms wrap around him, pulling him close. His nose fills with a familiar smell, as callused fingers rub soothing circles across his plastron.
"I am here," Master Shredder whispers in his ear, stroking Leo's temple. "I am here, hush. You are safe."
Yes. Yes, he's here, in their bed, in their chambers. Here with his master, who's kissing his head and rocking him back and forth, keeping him safe from the world. Leo leans into that touch, letting it ground him until he can breathe again.
The room around them is silent and dark, lit only by faint moonlight from a high window. It's just them tonight; Leo thinks Mistress Kitsune might be off somewhere with Alopex. And there are no rats.
"What happened, child?" Master asks gently, settling Leo back onto the pillows.
"It was him," Leo rasps. "It was the rat, he--he killed them again, and..." He swallows hard. But his entrance is not ravaged the way it was in the dream. It's slick and untorn, still a little loose from where Master took him after they went to bed.
Suddenly embarrassed, he looks away, rubbing a stray tear from his eye. "It--it was just a dream. I'm sorry I woke you, Master."
"It's all right," Master says soothingly. "We all have bad dreams." He lifts Leo's chin with a finger, forcing him to meet his kind eyes. "And you don't have to call me Master here."
"Yes...Daddy." He blushes as he says it, still self-conscious of how very dirty the word feels in his mouth. It's kind of uncomfortable, really, but he reminds himself it's a special privilege. Besides, his blushes always make his master smile.
"That's right." He leans down and gives Leo a soft kiss. "We're going to kill him, you and I. Him and his whole rotten family. We'll burn their kingdom to the ground and make love among the ashes."
Leo closes his eyes, drinking in his Master's words. He's right, of course. They'll kill the rat, his brothers will be avenged, and he'll redeem himself. Everything will be okay.
"Now," Master shifts his position, gently nudging Leo's legs apart. "Let's give you something else to think about, shall we?" He sucks a finger and slips it between Leo's legs, gently opening him back up.
Doubt flickers through his head--he's tired, he doesn't really want to be reminded of the way the rat straddled him--but he shoves that aside. Master's just trying to help him, after all, and besides, it always feels so good.
So Leo wraps his legs around his master's waist and lets himself be filled. He churrs and trembles the way Master likes, letting out soft little sighs for his daddy. Those deadly hands are so gentle on his skin, filling him up with warm, sweet pleasure.
"You're mine," Master whispers. "Mine, always, and I will never let anyone else have you. Do you understand?"
"Y-yes, Daddy," Leo rasps. Master kisses him again, hungrier this time, drinking down Leo's moans. Leo clings to him for dear life as they rock towards oblivion, feeling more loved than words can say.