The siblings' game of cards turns heated as they accidentally brush hands. The brother's eyes linger on his sister's flushed face, her lips slightly parted. He feels his cock twitch, imagining her mouth around it. She notices, her gaze flicking down to his growing bulge. She licks her lips, making his heart race. He stands, towering over her, his hands reaching for her shoulders. She tilts her head back, surrendering to his touch. He runs his thumbs along her collarbone, feeling her pulse quicken. She shudders, her nipples hardening against her shirt. The room grows warmer, their breath mingling, as they edge closer to the inevitable.