The adventures of a Demon King who awakens 500 years after his defeat in a futuristic world.

Aoba lives on Hekishima, a small island to the southwest of the main islands of Japan. He lives with his grandmother Tae while working part time at a junk shop. The popular pastimes on the island are the ongoing turf war called "Libstease" and an online game set in the virtual world of "Rhyme." Aoba isn't involved in either, preferring to live peacefully, until one day he is forced into a Rhyme battle.