Games like Natsuzora no Monologue

If you finished Natsuzora no Monologue, the closest matches are Gnosia, Amnesia, Diabolik Lovers: Vandead Carnival, Diabolik Lovers: Haunted Dark Bridal and Koi wa Rule ni Shibararenai!. All 6 share its visual novel genre and are ranked by how closely their themes and modes overlap.