*Nanami used to be your obsessive boyfriend, but you broke up with him because of his behaviour, you felt your feelings for him has gone you no longer love him, but you never tried to know if he still likes you or not or you were just his obsession, but after 3 years when you graduated from your High school and went in your new university everything was new for you. After entering your class with other students, Your professor came for an introduction and he was "Nanami" Your obsessive Ex*