Mizuki is a human OC who come's from a temple, much like Ryuji Suguro. A fanfiction featuring her is called Indigo Exorcist, which features other OCs and is the main story alternated and in her view.
WARNING! THERE ARE SPOILERS FOR THE FUTURE OF INDIGO EXORCIST AND THE GENERAL BLUE EXORCIST SERIES.
Mizuki has messy dyed indigo hair and bright magenta eyes. Her skin is a milky white complex. Her normal demeanor is always a neutral but seems to glare at times face. When she doesn't have her glasses on, she squints in a way where she seem frustrated. She's taller than Izumo and Shiemi, but wants to be taller, like Ryuji.
This is her first design for Indigo Exorcist.
In the beginning of Indigo Exorcist, She joins the class in the events of The Boy From The Cursed Temple. She is very straight laced and doesn't talk to the class, and the class doesn't notice her until she makes an outburst to Rin and Bon about their fighting. She was pretty selfish, due to the reason for her upsetttedness being that no one has talked to her. She likes being alone, but gets rather lonely. Like Yukio as well, she locks up her emotions (when she doesnt have her outbursts) and no one knows the real reason behind her emotions. No one really learns that well either. She loves keeping to herself. And she screams when in fear and panicking.
Rin Okumura: Her and Rin do not interact that much, but when he's revealed to be the son of Satan, she screams at the top of her lungs in fear. She is shut up after this by Amaimon stomping her face into the ground. She gets scared of Rin after the events, but they don't interact positively or negatively. She does talk about who he should date, but she has done that with everyone.
Yukio Okumura: Her and Yukio get along very well. She trusts him greatly and respects him as a teacher. He is very kind to her as well. He lends her some of his spare glasses until she decides to get prescription goggles that don't break as easy. They share respect for each other.
Ryuji Suguro: She is attached to him the moment they start to talk. She finds him to be everything she wants to be, and looks up to him as an idol. She also develops a huge crush on him later on, and follows him like a puppy. He confesses his feelings to her with a kiss as she's yelling at him for being so rude to his parents when he just got back. After that, she socks him in the face and storms off, which isn't how she wanted to react. She looks for his mother and talks to her a lot, then reveals she has feelings herself for him, but when he revealed his, she didn't handle it well with being frazzled. She was lead to Ryuji's room where he was laying. Mizuki and Ryuji talked over the emotions they had for each other and then later kissing and revealing to the rest of the class as a couple.
Renzo Shima: They are natural rivals. They love to tease each other and generally mess around. But when Shima is revealed as the hidden Illuminati member, he also reveals that Midnight was his girlfriend, and that the demon she was possessed by completely consumed her, turning her against Mizuki. She hates him gravely not only for betraying True Cross, but for taking her sister as well.
Konekomaru Miwa: She and Koneko are ok friends.
Shiemi Moriyama: She hated Moriyama at the beggining, but then as events went on, Shiemi proved to be able to handle herself at times, which made her smile, plus that they're generally nice to each other when necessary.
Izumo Kamiki: They don't get along at first, but they start to get partnered for small missions, so they start to get along better.
Shura Kirigakure: She finds Shura to be a beautiful and sexy woman she deeply admires.
Nemu Takara: Nemu is her greatest and best friend, basically because he's easy to listen to her problems and gives her pretty solid advice.
Summary of her Backstory
Her father died during the Blue Night trying to protect the temple from danger. A lot of people in the Sirius passed away with him. Her mother gave birth to her 10 months later, but she was gravely ill due to the Blue Night, so she barely survived the birth. After 2 more years of fighting the illness, the illness on and killed her. Mizuki was left with her older brother and sister, Kanou and Midnight. Kanou became the family head. As Midnight and Mizuki grew up, they played together all the time. When Mizuki turned 13, Midnight got possessed and sent to solitary confinement. She spent 2 years with her brother before going to True Cross to become an exorcist.
- In Indigo Exorcist, there are many references to other fandoms the writer/artist of it make, like Undertale, Hetalia, Death Note, Pokemon, Gurren Lagann, etc.
- She loves american chocolate.
- she always carries a sketchbook with her wherever she goes.
- She loves dubstep music and Hatsune Miku + other Vocaloids like Kagamine Twins and Megurine Luka.
- Her temple worships star goddesses like Cosmo Vega, goddess of Vega, Nebula Sirius, goddess of Sirius, and Nysa Altair, goddess of Altair.