As the water pours over their bodies, the siblings' inhibitions wash away. The sister's nipples harden, her breath hitching as she watches her brother's cock grow. She leans in, her tongue darting out to lick the tip, causing him to groan. He reaches out, grabbing her ass and pulling her closer, their bodies sliding against each other in the wet heat. She takes him into her mouth, her hands exploring his body, as he fucks her face, the sound of their pleasure filling the tiny space.