The ancient text lies open on the stone altar, its pages yellowed with age and worn thin by the countless hands that have touched them. The siblings kneel before it, their eyes scanning the ritual words that they know by heart. As the full moon casts its silvery glow through the stained glass windows, they begin, their voices barely above a whisper. The air grows thick with tension as they remove their clothing, their bodies bare and vulnerable. They stand before each other, their eyes locked, as they prepare to offer themselves to the dark god of their desire. With a shuddering breath, they come together, their bodies merging in a frenzy of lust and desperation, their cries echoing through the empty church as they seek release from their eternal torment.