As the storm rages outside, so does the tempest within the isolated cottage. The siblings, huddled together for warmth, can no longer resist the magnetic pull between them. Her breath catches as he traces the curve of her hip, his touch igniting a fire within her. He growls, his voice barely audible over the howling wind, "We shouldn't..." but his words trail off as she silences him with a kiss, her tongue delving into his mouth, hungry and insistent. The room fills with the sounds of their gasps and moans as they succumb to the primal urges that have long been simmering beneath the surface.