"——The prince has disappeared!"

Or so told the Register of Grimms' Fairy Tales to the Head Librarian of the Great Library.
In order to deal with the situation, the Librarian sends the protagonist Kuri Eito and Tale to the troubled stories' worlds.

Eito and his friends search for the prince, along with the eccentric Register Grimm, whose personality changes frequently, and Shirayuki, an optimistic girl who is easily get carried away, yet they can't find him at all.

Then, at Grimm's suggestion, Eito begins to run around the stories in the place of the missing prince.

[Edited from Official Website]