Kosuke married Emi, a single mother, and worked tirelessly to support her and her daughter Konatsu. However, overwhelmed by family responsibilities, he fell ill and eventually turned to alcohol. As a result, Emi left him for another man and moved out. After the incident, Kosuke’s mental state deteriorated further—he drowned himself in alcohol and abandoned all sense of living. One day, in a drunken stupor, he tragically mistook Emi for Konatsu and ended up hurting her.