After my husband came to work, I was always alone with my father-in-law ... Oba Yui

The movie revolves around the protagonist, Oba Yui, who lives with her father after her husband starts working. Her mundane life takes a turn with the arrival of Jiang Wei, her cousin, who comes to stay with them. As they start living together, Jiang Wei's presence brings excitement and temptation into Oba Yui's life, leading to a forbidden and intimate relationship between the two. The story explores the development of their secretive and passionate bond, despite the societal norms and family dynamics that surround them.