The voice coming from the Black Shinkansen, "Phantom Shinkalion", belongs to the missing Ina. Taisei is so shocked that his Aptitude Value drops and he is no longer able to ride the Shinkalion.While Akane, Ryota, Ten, and Shion set off to various places to defeat the Unknowns that have appeared across the country, Taisei, whose Aptitude Value has not yet recovered, traps himself inside the Metaverse.Then, someone appears before him.