Now that Ash has completed his first few projects in Itsutsu, the time has come for him to tackle his next goal: creating an accurate world map. To get there, he'll need to develop mapmaking tools, gather piles of data, and even calculate the width of the world.

In the end, Arthur offers to helm the project, and with every successful step forward gains confidence and hope for the future. But just as things are looking up, Maika notices a shift in Ash and Arthur's relationship that leaves her in an emotional tailspin. Will she be able to voice her feelings and solidify her place at Ash's side? Or will she end up losing his heart to someone else...?