One afternoon, a young man returns home and reunites with Yuriko, his mother's former classmate. Watching her and his mother, Ai, flipping through an album and reminiscing, he exchanges greetings with them. At that moment, he feels a strange sense of familiarity in her gaze, as if he's seen her before. This look is coming from Yuriko, his mother's friend. But it's not just him—Yuriko's son is also experiencing a similar unease. Under the knowing, suggestive glances from mother Ai, both young men gradually begin to feel confused. Soon, their relationships deepen, evolving into intimate encounters between Yuriko and Ai with the sons in the bathroom and bedroom. This intense web of connections ultimately delivers a profound shock to both sons.