An Onoya is a third year student at the school Kaizaki attends after she becomes a teenager. She is a transfer student like Kaizaki. Later it is seen she's an employee of ReLIFE Support Division like Yoake.
Onoya is a petite, young girl with light brown hair worn in braids and red/pink eyes. She wears the 3rd year uniform with a red lapel that all third years wear and wears glasses.
Onoya has a cheerful and bright personality, often seen with a bright smile on her face. Behind this cheerful front, she has a manipulative and cunning personality as seen when she tries to seduce Kaizaki just to see how he would respond and pretending not to know Yoake, even though he is her senior at ReLIFE.
She is seen discussing about her first subject at ReLIFE with Yoake.It is seen that her first subject for the ReLIFE experimentation was Kaizaki Arata. She discusses his current job situation and his trauma and concludes that being surrounded by third year students will make him regain confidence. She watches him closely during his part time job at a departmental store. After witnessing his dedication and kindness, she along with Yoake feels that Kaizaki would be a perfect candidate for the ReLIFE Experiment.
After being introduced to Kaizaki as a ReLife Employee, she tells him that she could not become his supervisor because she failed to complete her training.
However this is shown to be a lie, as she was selected to become Subject 001's supervisor due to Yoake's failure to make their ReLife a success.
At the first glance it seems she enjoys messing around with Yoake's work and to tease him at every opportunity. However, as her superior, she has great respect for him and she is always genuinely concerned about his well being when things go wrong. In addition to her constant teases, it is also hinted that she does have a bit of a crush on him as Yoake states that Arata was able to easily pat Chizuru's head before due to him regarding her as a kid, which reminded Onoya of when Yoake patted her head. The thought of Yoake regarding her as just kid therefore seems to bother her .
Using her position as a member of Support Staff, she loves to tease Kaizaki regularly, specially when the other test subject is concerned. He is bothered by her presence most of the time. However, she's very worried about the effects the end of the experiment will have on him.
At the start of school year, she had minimal interaction with Hishiro. Hishiro constantly calls her "Braided-Glasses Girl" and is irritated at her being close to Kaizaki. It is later found out that she does this intentionally so that she can induce some jealousy in Hishiro. Afterwards in the second term, she was introduced as the supervisor for Hishiro. Onoya wants Hishiro to successfully complete her ReLife but she is saddened by the effects of the end of the experiment on both Hishiro and Kaizaki.This is because she sees Hishiro having Kaizaki as a moral support and feels after losing her memories, she would go back to being anti-social as she was before her ReLife.
- ↑ Chapter 152, Pages 19-20