Bundled up in their winter gear, the siblings huddle close for warmth. As the storm rages outside, their bodies heat up, their hearts pounding in sync. The sister's gloved hand brushes against her brother's crotch, feeling his growing hardness. He responds, cupping her breast through her thick jacket, making her gasp. They grope and grind, their breaths coming in rapid puffs, the cold air contrasting sharply with their burning desire. Soon, they're a tangle of limbs and clothing, their bodies yearning for the forbidden, the blizzard forgotten.