As they huddle together in the dark, the siblings' innocence begins to slip away. The girl's fingers trace the outline of her brother's cock through his pants, feeling it throb with anticipation. He, in turn, cups her breast, thumbing her nipple until it stands erect. Their mouths meet in a passionate, tongue-filled kiss, as their hands explore each other's bodies with growing desperation. Despite their misgivings, they can't deny the intense pleasure they find in each other's arms.