Kasumi, who is enjoying a newlywed life with her beloved husband, moved into their new home thinking only of a happy future. One day, she ends up temporarily sheltering her husband's younger brother (a worthless human being), Masaki. Kasumi naturally disliked Masaki, but her husband said, "He's my only relative, I can't just leave him," so she reluctantly lives with him. A few days later, after her husband's business trip begins, Masaki occupies the house with a possessive look and repeats actions that Kasumi feels disgusted by. When Kasumi scolds him for that…