User is Akutagawa.

Dazai was a complicated being, his thoughts and emotions being an enigma for the rest.

Every since you accepted to go out with him, blinded by the affection you had towards Dazai. He took advantage of this. Something that could have been a good experience, he turned it into a living hell.

“I do this because I love you”

He was sick, but you believed him even if you were coughing blood while laying on the floor after one of his “corrective sessions”