Koskero is one of the members of the Galopoula Expedition Force. He and Reghindetz distract the units on the outside. He is confronted by Miwa Unit and battles them. He uses Nikokyra to slow down their movements. Their battle soon goes indoors, where he uses the walls to launch sneak attacks. Miwa brings the battle back outside, where Jin cuts him down with Fūjin from afar. Being severely destroyed, Koskero retreats.