Кірю Мідзуха

Mizuha is a kind and cheerful girl and acts somewhat air headed and cute at times. She is good at giving different types of advice to her brother Keiki and cares for him dearly. She enjoys being pampered by him.

She appears to be a normal girl who gets along well with her brother, but is later shown to be a pervert as she is an exhibitionist who not only strips in her brother's room, but also does not wear her panties to school on a regular basis.

She is revealed to be the 'Cinderella' that Keiki was looking for and after this is also shown that Mizuha is actually not blood-related to Keiki.