Black Kanojo

Teru Hoshino was just a typical sophomore in junior high school who had to put up with the teasing of his childhood friend, Amamiya. She was well-known at school for having large breasts, but Teru didn't let her harmless bullying affect him too much - his life was fairly uneventful, as far as he could recall. However, everything changed when Amamiya's behavior became inexplicably strange, and Teru was suddenly thrust into a disorienting and unsettling new world.