Active Raid: Kidou Kyoushuushitsu Dai Hachi Gakari 2nd EP4 - Mythos, Once More

Kuroki wants badly to rehabilitate Mythos, the young boy caught up in the Logos incident. When an unmanned bike starts making strange appearances on the roads of Tokyo, he sees his chance to allow Mythos to contribute to society by solving the mystery. The bike appears and disappears without causing any harm or hurting anyone. But Mythos thinks that instead of a bored thrill-seeker, the culprit might be a more dangerous foe...