Jin and Akira are given the task to seal a rip in time that's tearing the demon world, Valhalla, apart. In order to do this, the two must use their own demons to fight and defeat the creatures that have been let loose, and repair the rift before time itself is destroyed.

DemiKids: Light Version has the player take the role of Jin as he travels the land in search of demons to fight and collect. There are 350 creatures in all to recruit, and the only way to collect all of them is by trading with DemiKids Dark Version.