The house was too quiet after midnight, the kind of silence that pressed against the skin and made every breath feel loud. Mark stood in the doorway of his sister's old bedroom, watching her sleep. At twenty-three, Emily still looked like trouble wrapped in soft curves, her tank top twisted up to expose the smooth plane of her stomach. He had come home for the weekend, but the years apart had done nothing to kill the hunger that had always lived between them.
She stirred when the mattress dipped under his weight. Her eyes flew open, wide and startled in the dark. "Mark? What the hell"
He didn't let her finish. One hand clamped over her mouth while the other pinned her wrists above her head. "Shh. Mom and Dad are asleep down the hall. You don't want them hearing this."
Emily thrashed, legs kicking, but he was bigger, heavier, and the years had only made him meaner with need. He shoved her thighs apart with his knee and ground against her, letting her feel how hard he already was. "You've been teasing me since you turned eighteen. Walking around in those tiny shorts, bending over in front of me. Time to stop pretending you don't want it."
She bit at his palm, but the sound that escaped was half protest, half something hotter. He yanked her tank top up, exposing her breasts, and sucked a nipple hard into his mouth. Her back arched despite herself. He released her wrists only to rip her shorts and panties down in one rough tug, then freed his cock, thick and already leaking.
"Mark, stop we can't" Her voice cracked as he pushed two fingers between her folds. She was wet. Soaking. The lie in her words made him groan.
"Can't? We're already doing it." He lined up and drove into her in one hard thrust. Emily's cry was muffled against his shoulder when he covered her mouth again. She was tight, hot, clenching around him like she was trying to push him out and pull him deeper at the same time. He fucked her with long, punishing strokes, the bed creaking under them, the risk of their parents waking only making him harder.
Every thrust forced a wet sound from her body. He leaned down, teeth at her ear. "You feel that? That's your brother splitting you open. Been dreaming about this cunt for years." He reached between them and rubbed her clit in tight circles. Her hips jerked, betraying her. She came with a choked sob, walls fluttering and squeezing, milking him.
Mark didn't stop. He flipped her onto her stomach, yanked her hips up, and slammed back in. The new angle made her gasp into the pillow. He gripped her hair, pulling her head back so he could watch her face while he used her. "Say it. Say you want your brother's cock."
She shook her head, but her body answered for her, pushing back to meet every thrust. He reached under and pinched her clit again.
Another orgasm ripped through her, stronger this time, and the feel of it broke him. He buried himself to the hilt and came with a low, guttural growl, flooding her with hot pulses.
They stayed locked together, breathing hard. When he finally pulled out, his cum leaked down her thigh. Emily rolled onto her back, eyes glassy, chest heaving. She didn't speak. She just reached for him, pulling him down for a messy, desperate kiss that tasted like surrender and sin.
Mark smiled against her mouth. "We're not done yet, little sister. Not even close."
