Not Horror: Nana Fushigi Tanteidan

Freshly moved to Daimon-machi, Tom Satou meets a mysterious young man named Kibayashi. Lately Tom has been troubled by something, and asks Kibayashi for advice. It's about this new "Seven Wonders School"... Tom has noticed a lot of phenomena that can only be thought of as supernatural. Upon hearing this, Kibayashi agrees to help Tom solve the mystery. Thus, the young friends begin their adventure.