Youmu has short silver hair and blue eyes. Youmu's outfit generally consists of a aquamarine vest and skirt over a white undershirt with several ghost insignias along the edges of the skirt and one on the breast pocket of her vest. She wears a black bowtie and hairband with black ribbon tied off-center in her hair. Her ghostly half is a white phantom as large as her human self, sometimes referred to as myon by the fandom.