Cutting(2007)

Cutting

Kazuya is a teenager who is worried about himself acting differently in his daily life then what his heart actually believes. One day he encounters Mio, a serious suicidal girl who slits her own wrist.

He is then attracted to her uncontrollably and the two became lovers soon after Kazuya's confession. After spending some time with each other, Mio's personalty is changed bit by bit, right before she was murdered...