Splinter dies first. It begins with a watery cough, then quickly dovetails into a raging fever. The hemorrhaging starts a week later. By then, their father is hardly more than a skeleton under thinly-stretched skin. When his heart finally gives out, it's almost a relief, though nobody dares say it out loud.
Leonardo never leaves their father's side, even when the stench of death permeates every room in the lair. He's inconsolable. And violent. Raphael has to forcibly restrain him from attacking Donatello when their brother finally comes to take the body away.
A couple of days later, Leonardo starts coughing. Donatello immediately orders him to bed in a tone that broaches no argument. Their brother is suspiciously compliant, which makes Raphael wonder if he'd known even then.
Donatello works tirelessly day and night, searching for the cure that would make their sibling whole again. But when science fails, so does he. The resigned look on his face speaks volumes, and Raphael knows the phlegmatic cough coming from Donatello's lab late at night is just the beginning.
His brothers come to him soon after, begging him to do something—the only one who can, they insist. It's the pleading look in Michelangelo's eyes that finally does it.
When he walks into Leonardo's room, the fetid, sickly smell coming from the bed makes Raphael choke. He can barely see his sibling's shriveled figure under the piles of threadbare blankets. He looks so small, so frail, nothing like the commanding presence of his true form.
Raphael sits on the edge of the mattress and stares at his brother's pallid skin. His mouth hangs unhinged, and his breath rattles weakly in his chest, like dry leaves in the wind. His hooded eyes stare unseeing into the middle distance.
"Leo," Raphael intones, but his brother doesn't stir.
Raphael sits back in thought. There's only four of them now, three if…but he refuses to allow the idea to carry further.
Family is everything. That their existence has been heaped with cruelty upon cruelty only makes it more so. He studies his brother's face. Would Leo want this? He can't be sure. They've never spoken about it, not even when Splinter was dying.
But they need their leader back. Their brother.
Raphael bends closer, his eyes shining preternaturally bright in the dim light. They follow the line of his brother's jaw, his neck, his throat.
A moment of indecision and then Raphael bites down, teeth piercing flesh. There's a soft resistance before his brother's lifeblood fills his mouth.
Raphael pulls insatiably at his sibling's throat. There's no rationale to the hunger; it's raw and primal. And nothing's ever tasted so good.
A feeble cry rises up from Leonardo's mouth. It vibrates Raphael's tongue. A hand flutters weakly against his plastron, the last vestige of some innate survival instinct. Raphael doesn't deny him this; instead, he pulls him softly against his chest, cradling his brother's head. Leonardo's fingers latch on to the outer ridge of Raphael's shell as if to push him away, but his hand soon falls and lands with a faint thump on the sweat-stained sheets.
Leonardo's heart stutters, surges forward, then slacks again. Raphael listens intently. He must be careful.
It's not long before the blood begins to slow, and Raphael knows it's time. He releases his brother, gently placing his head on the pillow. Leonardo's eyes are closed and unaware.
Raphael waits.
A final, faint breath passes between his brother's lips. And then…nothing. No movement. No sound.
Steeling himself, Raphael raises his wrist to his mouth. A sharp flair of pain and it's done. Droplets of blood patter on the sheets as he lowers his hand over his brother's mouth. But the blood flows uselessly down Leonardo's chin and onto the pillow. Stifling the gnawing anxiety in his chest, Raphael tilts his brother's head up and back, forcing the blood further down his throat.
Minutes pass and a candle burns its life away, leaving the room that much darker.
Lightheaded, Raphael leans over his brother's still body until his forehead touches the cool bricks of the wall behind the bed. He closes his eyes, trying to ignore the growing certainty that he's too late, that his brother is too far gone to survive the change. He breathes out a tremulous sigh and a tear slips down his cheek. He knows the others are waiting just outside the door. Waiting for him to save their brother. To save them. Raphael buries his head into the crook of his arm and cries quietly.
Time winds down and only the fiery pain in his wrist keeps Raphael tethered to the now. He's already given too much of himself and his other brothers will soon have need of him too. Feeling spent and anemic, Raphael finally pulls away and opens his eyes.
And sees Leonardo staring at him.
The light in his brother's eyes is strong and shines as bright as Raphael's own. Unblinking, Leonardo slowly reaches up and grasps Raphael's wrist, pulling it tightly against his mouth. His teeth are sharp and demanding.
Leonardo begins to feed.