Sounds of Regret M3: Sono Kuroki Hagane : Season 1 Episode 14

While the Lightless Realm continues to expand, the whereabouts of Akashi Saginuma remain unknown. Iwato and the other students left behind find out that they are known as the “children spirited away”. As the reasons why they were gathered together become more apparent, Mahmu decides to pilot Sable, the second machine, in order to grant Emiru's wishes.