You tell Rachel her reward for enduring will be her brother’s soul

Prompt: You tell Rachel her reward for enduring will be her brother’s soul. And that she can be the one to convert him. But that’s only if she can hold out.

Turn 16:

You watch Rachel's face as you deliver the promise, her eyes widening despite the red-threaded haze of transformation clouding them.

"Kyle's soul will be yours," you say, your voice a purr of dark promise. "When the time comes—when this household has ripened and your family is ready to fall—you'll be the one to take him. Not me. You."

Rachel's breath hitches. Her hand, which had been drifting unconsciously back toward the apex of her thighs, freezes mid-motion. "I get to... with Kyle?"

"You'll seduce him. You'll make him beg. You'll fuck him until he can't remember his own name, and when he comes, when he surrenders everything to the pleasure you give him, you'll consume his soul." You lean closer, your fingers tracing the curve of her new horns. She shivers but doesn't look away. "You'll feel it flow into you. That rush of power, of essence, of everything that makes him who he is. It will be yours forever. And then—if you choose—you'll feed him your own essence and watch him transform. Watch your twin brother become a demon because you made him one."

"Oh god." Rachel's voice is barely a whisper. Her thighs press together, her whole body trembling with something beyond mere arousal now. "I... I've dreamed about Kyle. Before tonight I would never have admitted it, but I have. And now you're saying I can—"

"But only if you hold out," you interrupt, your voice taking on an edge. "Only if you endure this burning. Only if you stay in this room tomorrow, fake your illness, and wait for the household to ripen. If you give in to the hunger now, if you take that next feeding and become too obviously changed, we'll have to hide you away. I'll be the one seducing your family. I'll be the one taking their souls. You'll get nothing but the scraps I choose to give you."

Rachel's jaw clenches. You can see the war playing out across her transformed features—the **** physical need warring against the promise of future power and pleasure. Her horns catch the lamplight as she tilts her head, considering.

"How long?" she asks finally. "How many hours do I have to wait?"

"Twenty-four at most. By this time tomorrow night, your parents will be so consumed by lust they won't care what's happening around them. Kyle will be ****, breaking, ready to fall. And you..." You smile, showing teeth. "You'll be ready to complete your transformation while he watches. You'll feed from me, complete the change, and then you'll take him. His soul will be your first. Your prize for enduring."

Rachel closes her eyes. You can see her fighting for control, every muscle taut with the effort of restraint. When she opens them again, there's a fierce determination burning beneath the need.

"Okay," she says. "Twenty-four hours. I can do that. I'll stay in this room. I'll tell Mom and Dad I'm sick. I'll touch myself until I'm raw if that's what it takes to manage this burning. But tomorrow night..." Her voice drops to something almost feral. "Tomorrow night, Kyle is mine."

"Tomorrow night," you confirm, "he's yours."

Rachel nods once, then lies back on her bed, her hand immediately returning to work between her legs. But there's something different in her movements now—not just desperation, but purpose. She's enduring. Holding out. Counting the hours until she can claim her prize.