Ruka began living with her stepfather after her mother remarried. He was kind, dependable, and had a wonderful relationship with her mother, and Ruka found herself drawn to their warmth. However, upon noticing Ruka's innocent, pure smile and her petite yet voluptuous figure, her stepfather crossed the line between parent and child, stealing a kiss from her lips. From that day on, he began desiring Ruka's body, starting a new, forbidden relationship.