Sakura, a widow raising her son alone, begins to rediscover her femininity as her son grows more independent. One day, her son's friend, Matsuda, asks her to play the role of his "mother" for just one day. As she takes care of him, their bond gradually deepens. Unable to suppress the unexpected emotions that arise, her awakened body begins to crave intimacy with him. Soon, Sakura finds herself drawn into a passionate affair not only with Matsuda but also with his friends. Lost in carnal desires, she becomes entangled in a secret web of lust—but vows to keep it hidden from her son at all costs.