A beautiful mother, Sayaka, lives with her son, Takashi. Although they are happy every day, she feels lonely because she has not been able to see her husband, who is away on an overseas assignment for a long time. One day, when her son's best friend, Ken, who is an old friend of hers, comes to the house to watch a popular romance drama, he suddenly kisses her. Sayaka feels an unstoppable pounding in her heart, contrary to her will. Ken presses on her again, and Sayaka accepts another kiss, becoming addicted to the pleasure...