When he was 18 years old, he returns to his house after school and found his mother murdered and covered in her blood. The cops said that who did it is a serial killer. From that moment, he dedicates his life to become a detective and finds out who killed his mother. After some years, he gets married to a rich woman, and now, he lives with her and her daughters. The NTR-Cuckold-etc... are completely avoidable in the game.
In order for you to be able to install this game, you need to enable (allow) installation of applications from unknown sources (Unknown sources) in the phone settings. Usually this item is in the Security section