Locked away in their tiny sanctuary, the siblings surrender to the darkness within. The girl, her breath hitching, guides her brother's rigid cock into her wet, waiting cunt. They move as one, their bodies slapping together in a rhythm as old as time. The room fills with their stifled moans and the scent of their combined lust, a symphony of sin that plays on repeat until they collapse, spent and ashamed, in each other's arms.