The game begins with your character living his life as a regular kid going to college. He’s adopted and sadly his folks are fighting and heading for a divorce. So you and your dad decide to move out and live with the dad’s strange girlfriend. Then your dad has to leave to handle some sort of weird job and his girlfriend begins to try to manipulate you and transform you into her puppet to do her will.
After this part of the game ends, the main character is now the girlfriend’s partner instead of the dad and you’re off to go to Tokyo and end up getting trapped by an evil drug company who doesn’t have your best interests in mind, so it’s up to you to decide your future.