She married Chio and lived in her husband's parents' house. Only his father-in-law and younger brother-in-law lived in his family, and the existence of Higeki, the only woman, was great. One day, a man with a mask appeared and Soki was killed. And it was Kiei, the youngest brother-in-law of a nephew who did not live at home, who took care of him. Kiei had been in the basement since he was suspected of being a lewd. Then, the dirty nature of the family gradually became exposed without knowing the culprit who committed the crime.