Father has invited his young mistress, Kokomi, over to the house, indulging in pleasure with her during the daytime. When his son, Masahiro, returns home and walks into the room, Kokomi feels a mischievous urge and begins seducing him. Drawn in by Kokomi's charm, Masahiro gradually falls under her spell. A dramatic tale unfolds, filled with conflicting emotions between father and son, and Kokomi's skillful seduction.