Chrome Shelled Regios: Missing Mail

In a future where pollution has led to the spread of mutated creatures, humans reside in mobile cities known as Regios. Zuellni, one of these cities, functions as a self-sufficient school. Freshman Layfon Alseif enrolls and joins the 17th Martial Arts Studies Unit under the leadership of third-year student Nina Antalk. This version presents an alternate perspective on Layfon's experiences, with Felli as the central character. The story shares the same world and setting as the original novel.