Super High School-Level Swimmer. Aoi is a warm, cheerful, upbeat, and outgoing girl who is friendly and welcoming towards everyone she meets, trying to make friends with everybody and include them in her activities. Aoi can be quite air-headed and forgetful, relying on the memory trick of writing peoples' names three times on her hand in order to remember them - a trick she also taught to her brother, Yuta. Due to being quite air-headed she can be easily manipulated by others and jump to conclusions or take them at face value, often being one of the few to fall for killers' tricks and misdirection during Class Trials. Aoi is an extremely athletic person and considers it an absolutely fundamental part of herself, using it as an important coping mechanism in her daily life and feeling like she "might die" if she can't exercise. Although Aoi is a star athlete in the running to become an Olympic swimmer, Aoi is insecure that being athletic, which is seen as quite a masculine activity, makes her undesirable to others and might lead to her never finding love. She's also concerned that her extreme sweet tooth, particularly her love of eating donuts, is going to make her fat.