Maki married a man with a son, Masashi, who initially treated her with cold indifference. Her persistence paid off when she nursed him through a high fever, finally opening his heart. One night, Masashi asks for a kiss, just like his late mother used to give. Though Maki tries to warn him that 'adult kissing is forbidden,' the heat of the moment takes over. This is the story of an alluring stepmother who educates her stepson in the arts of pleasure.