Yashiro is humanoid and white in color with dark facial features, similar to Rin. Wrinkles around Yashiro's cheeks, chin and neck suggest that he is aged. His temporary soul also suggests this, as it is visually less distinct and slightly unsaturated, as if it is old or weak.
Yashiro only appears once ingame, which is during the opening cutscene. He is seen giving Rin a temporary soul that will last for "forty-nine days." However, there is no apparent passage of time during the game, and at no point does the soul expire or become unusable.