Mikoko Aoii (葵井 巫女子 Aoii Mikoko) is a student of Rokumeikan Private University and an aquiaintance of I.
Mikoko is a fairly normal girl who usually has a high temper, and will hit anything nearby randomly. She owns a Vespa (vintage model) and calls it "scoot". She likes to use exaggerated metaphors and will take her clothes off when drunk. She has a crush on I and is friends with Tomoe Emoto, Akiharu Usami, and Muimi Atemiya.
In reality, Mikoko has an obsessive love for I, willing to murder her friend in cold blood just to prevent her from getting close to him. While the cause for her obsession is never revealed, I says that she just misunderstood him, and created an image of him in her mind that she projected on him.
According to I's assumption, Mikoko is about 155cm tall and weighs 50kg. She has short red hair and red eyes.
- Mikoko's last name, Aoii, is written with the characters for "hollyhock" and "town" (葵, Aoi = Hollyhock; 井, I = Town, Community, Well).
- Mikoko's first name means "shrine maiden's daughter" (巫女, Miko = Shrine Maiden; 子, Child).
- When Mikoko showed animosity towards Miiko Asano, I thought it was because their names were similar, as Miiko's first name is similar in pronounciation to the word Miko, meaning "shrine maiden".