In the confines of their stuffy attic, the siblings, bound by faith and blood, succumb to their lustful urges. The girl's fingers trace the outline of her brother's cock through his thin pajamas, feeling it grow hard at her touch. He, in turn, cups her breasts, teasing her nipples until they're rock hard. Their bodies press together, their hips moving in sync, simulating the act they both crave but dare not speak of. Their hearts pound with fear and exhilaration as they teeter on the edge of sin.