Hachigatsu Kokonoka Boku wa Kimi ni Kuwareru.

My grotesque (stalker), protects me from 100 stalkers in order to eat me. Sakurai Aoi, a high school boy, has a secret that he can tell no one. He's been a victim of stalking since childhood. One day Ueda Miyako, a classmate, suddenly turned into a monster. She was the one who was stalking Sakurai.