|Quotes | Relationships|
|School||Yasaka High School|
|Occupation||High School Student|
|Affiliation|| Kanetsugu Gasou |
|Japanese Voice||Satomi Sato|
|English Voice||Jeannie Tirado|
Mari Mizuno (水野 鞠, Mizuno Mari) is one of Aki Adagaki's self-proclaimed body guards who doesn't particularly like Masamune. She is the brains of all the schemes against Masamune and has two cronies, Kikune and Kaneko.
Mari has short black hair in a bubble bob haircut along with bangs parted to the right above her blue eyes. She may seem a bit shy though she is pretty intelligent, even looking the part. She wears red glasses and a white headband as well.