Teasing Game

Ayato Naoi, the student council vice president, unexpectedly falls inlove with the most unexpected person. He found out that there was another human living in the afterlife besides the SSS. He eventually befriends her and they become really close, and slowly develops feelings for her, much to everyone's surprise. There's one problem: She has amnesia. She remembers nothing about her past. That's where Naoi comes in.