The Takasugi family became a father-son family with one parent and one child after their mother died three years ago. Her father works hard for her daughter, and her daughter, Mari, is growing up healthily, and they live happily together every day. However, Mari eventually begins to feel more than a parent and child toward her father, and spends her days thinking of her father and comforting herself and cooling her body. One day, Mari's desire finally explodes when she can't hold back her feelin...