Dengeki Gakuen RPG: Cross of Venus Special

It's an enhanced remake produced in commemoration of the fifteenth anniversary of ASCII Media Works light novel imprint Dengeki Bunko.

The player assumes the role of an unnamed protagonist attending Dengeki Academy who stumbles into a fight between heroines from Dengeki Bunko novel worlds and the evil organization Zetsumu. The reality-based world of Dengeki Academy and the novel worlds have become connected and the player is able to help the Dengeki Bunko heroines fight the Zetsumu by going between the worlds.

Summary: IGDB