Heikou Sekai no Jibun ga Konomi no Bishoujo de Kuse mo Onajidattanode Koishite Shimatta

Asahi, a boy who likes stories with bad endings, meets Tsukino, a beautiful girl, at the movie theater. She loves bad endings just like he does, and the two hit it off immediately. Reluctantly, they eventually said goodbye and went their separate ways… only to find themselves both ending up at Asahi’s house, and Tsukino claims she lives here, too. It wasn't like that this morning, and Tsukino seemed completely unaware of Asahi's situation!? After investigating, Asahi was forced to conclude that Tsukino is actually the same person as himself in a parallel world — and she had somehow wandered into this world. Asahi agrees to help Tsukino return to her original world, but he can’t help but be drawn to a girl who’s exactly his type — and Tsukino seems feels the same way… A romantic comedy woven between two people who are just a little too much alike! (Source: Dash Bunko, translated)