Kyuuketsuki ni Natta Kimi wa Eien no Ai wo Hajimeru

In May of his first year in High School Harada Utaya became a something that's not a human being. He gained inhuman athletic abilities and was unable to continue play his beloved basketball. He changed schools and there he met a beautiful - Virgin Mary-like senior named Harushina Ayane who asked him to be her "lover" Dracula in a play?!