Merihim was one of the Nine Eternal Divine Scales, the nine great Crimson Lords gathered under the name of Töten Glocke, the organization led by "Weaver of Coffins" Asiz. During the Great War, he was partnered with Illuyanka, and the two were known as the "Pair of Wings". After the Great War, he stays at Tendōkyū as the skeleton Shiro, serving as a trainer for the girl who would become the next "Flame-Haired Burning-Eyed Hunter". (Source: Shakugan no Shana Wiki)