Humans and demons have agreed to live in harmony with each other, and the first step towards that goal is allowing succubi children to attend to human schools as some sort of program to study abroad. Of course, the succubi will have to obey the human rules, but humans will also have to adapt to the necessities of their new neighbors, which usually involves spicy things.

A crossover telling the story of the Z Fighters as they get sent to different worlds and must team up with their respective inhabitants to find a way back home. Meanwhile, Xellos, a Mazoku serving the Demon Lord Shabranigdu, teams up with the Super Saiyajin created artificially by his own father, so they can find "vessels" across different worlds.