Zettai BL ni Naru Sekai vs Zettai BL ni Naritakunai Otoko

One day, the protagonist realizes that he lives inside a "world of BL." As he likes girls, he fights back against any hot guys that might draw near, but this is a "world of BL"... he's still assailed with the sight of people in lovey-dovey situations one after another! (Source: MyAnimeList) ~~ Adapted from a manga of the same name.