After School-A Vocaloid RPG is a survival-horror Vocaloid RPG experience created using RPG Maker VX Ace. Playing as Oliver, you find yourself in a "Spirit World," an alternate dimension hosted by a single corrupted spirit. You meet new characters, and help spirits along the way while keeping an eye out for the corrupted host spirit. The player must help Oliver escape this world safely, while navigating the dangers it throws his way. Heavy inspiration was taken from games such as End Roll and Ib, while the initial inspiration to start this project was taken from the song "Crushed Mary" by Mondaiji-P.

Oliver spends a lot of time wandering around the desolate side of town. When a heavy downpour starts, he stumbles upon a school he's never seen before.