In the sultry heat of a Spanish afternoon, siblings, too tired from their family's arguments, retreat to their rooms. The brother, hidden in his room, listens to his sister's soft moans as she masturbates, imagining her fingers exploring her wetness. Their mother's shouting only intensifies their desire, and they can't resist the urge to join each other in their shared lust. The brother, hard and eager, watches his sister touch herself, her body glistening with sweat and desire. But their moment is cut short as their mother's footsteps approach, forcing them to hide their sinful encounter.