Mika has soft, deep blue eyes and knee-length hair that is worn in a low side-tail held with a black and silver ornament. Her bangs are mostly brushed to the side with a small tent at the corner and a few curling loose strands. She hears gold star earrings.
Mika is normally shown in a dark blue gradient dress with a pattern to resemble the evening sky, covered in tiny white dots, stars, and lines to resemble constellations. The bottom is lined in silver. Sewn to the skirt is a white sailor collar with dark blue lining to match the included tie and arm sleeves. Four colorful buttons adorn each sleeve. She also wears black tights and split colored silver and dark blue pumps with a ribbon strap attached to a gold star charm.
In the anime her outfit has tiny modifications to it.
Mika is a gentle and hope-filled girl with a wide-eyed innocence who is normally calm, but she is easily excited.
- Mika's surname Kozuru means "small" (小) (ko), "water" (水) (zu) and "flow" (流) (ru).
- Chinatsu Akasaki (Mika's voice actress) shares the same name as Chinatsu Ryuusekidou.
- Mika's birthday is July 2nd.
- Mika's blood type is B.
- Mika loves to stargaze.