When my daughter Ichika got married, I, a doting parent, remodeled the house into a two-family dwelling. The cohabitation was harmonious, and I had built a good relationship with my son-in-law Shinji. However, everything changed from that day onward. My wife Fuyuka started going to the newlyweds' side of the house more often for any excuse, and she claimed she had made an impossible promise with our daughter. But Ichika began telling unnatural lies, saying she never made such a promise...