Togo Jun and her younger sister Mishima Ran meet again for the first time in 13 years at the funeral of their mother. Since Jun was a child, her free-spirited younger sister, Ran has taken away important things such as her favorite clothes, accessories, and toys. What's more, Ran even married Jun's ex-lover, Ritsu Mishima. Since Jun can't let Ran take away anything more precious to her, she decides to live with them both. Gradually, the sisters engage in a fierce battle over one man!