Ken Mayuzumi is a character who works as a hair and makeup artist, with his office located in Production Room No. 3 at Star Harmony Academy. Beyond styling, he also takes on the role of a choreographer. He has curly blue hair that is cut longer on the right side of his head, with a dark yellow streak running through his bangs and small curled strands sticking out from the side. He has rounded topaz eyes and wears a red earring.

Ken is very passionate about both dance and the beauty arts. He is also shown to be very caring toward his fellow colleagues and the idols he works with. Regarding his role in the story, he is a staff member at the academy who supports the idols from behind the scenes. His notable abilities include his expertise in hair styling, makeup, and choreography. No information is available about his specific motivations, key relationships with other characters, character development over the course of the series, or detailed background beyond his occupation and workplace.