"Ayane-chan, will you marry me?" A sudden proposal from a childhood friend who is 10 years younger than her? --- Ayane Kakihara, 34 years old, is actively looking for a marriage. She just got dumped on a date today, saying, You don't need a man for the rest of your life, do you?'' Her mother called and said, I've sent you a good person,'' and the person waiting in front of her house was her childhood friend Itsuki. Ayane is confused by the sudden proposal from a man who has even changed her diaper. Although she refuses because he sees her only as her younger brother, she has a soft spot for Itsuki, whom she has always loved. She allows him to live with her for a week and approach her every day. A week has begun where you will be at the mercy of the trees that will approach you if you give them a chance!