This costume pack features the 12 members of the Taranis crew in Japanese school attire.
You can modify what the children are wearing under "Change Costumes" in the Options menu.

Contents:
Back to School Costumes for Malt, Mei, Hanna, Kyle, Boron, Socks, Chick, Hack, Sheena, Jin, Wappa, and Britz (can be used during intermission and expedition)

More details on the official game page of Fuga: Melodies of Steel - Back to School Costume Pack ...