Tadashi Ore wa Heroine Toshite

A 30-year-old virgin, obsessed with R-18 dating sims, visits a deserted shrine after the company that made them goes out of business. He wishes to enter the world of Kokorone Heartful, the company's most popular game. A deity grants his wish but makes a mistake, transforming him into the game's heroine instead of the male lead. In the game, the protagonist typically makes romantic decisions, but since he is now the heroine, he must finish the game from her perspective. If he fails to complete it as the heroine, he will be stuck in the game as a woman permanently.