A cruel fate testing the bonds of sisterhood... 'Sister Momo and Sister Karin' begins with the setting of two young ladies from a wealthy family being taken in by their uncle after the sudden death of their parents. The uncle, who seemed kind at first, shocks them the next day by waking them up naked and handcuffed, unleashing his hatred for their father. Under the harsh condition of competing in sexual servitude to the uncle, with the loser being kicked out of the house, the sisters' egos and survival instincts clash. The collaboration of powerhouse actresses Kitaura Karin and Shiraishi Momo vividly portrays the ugliness of human nature and eros, leaving a strong impression on viewers. Particularly, the scene where the two compete for a single 'meat stick' is a highlight, showcasing their personalities and sex appeal to the fullest.