Yamamyu is an anime-style character with fair skin. He has messy, short black hair with brown undertones, styled with some strands pulled back and secured with a large blue snowflake accessory. Several scratches mark his forehead and dark streaks run from his lower left eye down his cheek. His eyes are large and round, with a striking deep purple color. He has a small, slightly smiling mouth. He's wearing a dark blue uniform with a stand-up collar, fastened with a gold button, and adorned with two white horizontal stripes on the chest. A purple jacket is worn over the uniform. While the image does not show his abs, nor mentions Emika, one can infer from the description provided that Yamamyu has a toned physique and holds affection for her.

Yamamyu is depicted with long, flowing hair that is primarily black with hints of red-brown towards the ends. His hairstyle features a long ponytail adorned with a light blue ribbon and a sprig of green leaves. He has fair skin and striking violet eyes that convey a serious expression; his eyebrows are slightly furrowed. His nose is small and his mouth is set in a thin, firm line, reinforcing his stoic air.

He has a muscular build, and his posture is upright with his arms crossed. Yamamyu is wearing a dark purple robe with black trim and lighter purple accents on the sleeves. An elaborate black and white belt cinches the robe at his waist. His hands are partially covered by what appear to be black wrist wraps.