Souma, Yuki's younger brother, vanished after the destruction of Lost city. He sports short silver-blue hair and crimson eyes, typically dressed in a choker, white coat over a gray shirt, pants, and shoes. His personality fluctuates with the use of a specific artifact: it renders him cold and blunt when active, but he remains cheerful without it. Written in katakana as ソウマ (Sōma), his name carries no inherent meaning. When expressed through the kanji 颯真, however, 颯 (sou) suggests 'sudden' or 'sound of the wind,' while 真 (ma) conveys 'real' or 'genuine.'