With help from a 102-year-old goblin dwelling beneath their haunted apartment building, two siblings deal with ghosts and take on spooky mysteries.

Koujirou moves to Tokyo from Japan's northernmost island of Hokkaido and insists on bringing his favorite horse, Hikarikin, with him. The alien king Rel arrives from planet Wedelun and gives him a belt that will allow him to transform into a Miracle Hero and to protect the world from alien menaces. He is more interested, however, in impressing the pretty Yuka, though his rival, Michinari, wants her for himself.

At the performing arts division of Seisho Music Academy, the ever-evolving stage threads the lives of its students together as they tirelessly hone their craft. Yet, as the girls prepare for a new rendition of the previous year's performance, the carefree Karen Aijou begins to settle for a smaller role. However, her waning passion is reignited by the return of her childhood friend Hikari Kagura, whose sudden transfer to the academy triggers a flurry of changes in the class dynamics. Subsequently, Karen chances upon a secret battleground underneath the school, which houses a set of auditions that will crown its ultimate victor as "Top Star." As she dives headfirst into these enigmatic trials, Karen begins to learn about the tribulations that come with vying for the top. Even if fate wills them apart, Karen and Hikari must fight in hopes of fulfilling their childhood promise: to become stars together. [Written by MAL Rewrite]