Sandwich Story

[MangaDex]

 

[BuyVelomobiles]

Man moves in with highschool girlfriend, highschool girlfriend starts treating him like errand boy. Man has girl friend he talks to. Girl friend asks man out. Man says he has girlfriend. Girl friend says she knows. Story ensues.

Ending is typical Hamita:

Spoiler: Swear to god, buddy, just write your endings better

Girlfriend was imaginary the whole time because she died just before she "moved in". Girl Friend knew but was still somehow surprised when the twist was unveiled. Had a crush on MC and was trying to help him get over her. MC gets treatment, and stops seeing girlfriend. We find out MC made up girlfriend because there's the ghost of his girlfriend is haunting him, and we're left with MC reassuring himself that she wouldn't resent him because "That was an accident" , and she's nice, with the ghost giving the creepiest fucking stare I've seen in literal years, if not ever. The implication obviously being that he had a hand in her death, but she'd forgive him.