Stepmother’s Past summary: Vivid moans between father and stepmother’s copulation, and the death of his mother who couldn’t stand the reality. Having witnessed all of this with his own eyes, Jaehyun lived with nothing but hatred for his stepmother. However, for reasons unknown, he discovers himself lusting while looking at her. A few years later, Jaehyun lost his father because of his stepmother. Unable to overcome the accumulated rage, he ravishes his stepmother’s body and immediately runs out into the street. A dump truck’s sudden appearance leads to his death. When he opened his eyes again, he found himself 23 years ago in the past. Back to the day of his biological mother, stepmother, and father’s first encounter…