Fire Force Graphic Novel Volume 31

The city of Tokyo is in the grip of a reign of terror! Possessed by demons, people have begun to burst into flame, leading to the establishment of a special firefighting team: the Fire Force, ready to roll on a moment's notice to fight spontaneous combustion anywhere it might break out. But the team is about to get a very unique addition: Shinra, a boy who possesses the unique power to run at the speed of a rocket, leaving behind the famous "devil's footprints" (and destroying his shoes in the process). Can the Fire Force discover the source of this strange phenomenon and put a stop to it? Or will the city burn to ashes first?