Back story: Ayano has suffered from a fictional type of insanity, referred to as the Aishi Condition, for as far back as she could remember, before meeting Taro Yamada for the first time.[9][10] As a result, she doesn't have the ability to feel emotions, empathy, or remorse, as it would be difficult for Ayano to enjoy any experience due to a sense that something is missing.[11] She doesn't feel guilt or shame for harming others; however, she can feel pity.[12][13] She knows what the general people consider to be "wrong", but doesn't care.[14]

Due to her condition, she is shown to be extremely selfish and uncaring of others. Caring about pursuing Taro, as she believes the one who made her complete is the only thing that matters to her, much like her mother. Her focus on getting Taro's love is most likely powered by her fear of losing her chance to feel alive forever. Ayano is also shown to be extremely delusional, believing that she is more worthy of Taro's love than the rivals because they could never love him as she can, as evidenced by when she saw Osana Najimi. Even if she did not trigger the Senpai effect, she would not date anyone. She is capable of nonviolent elimination methods in order to cause less stress for Taro or to run less of a risk of getting caught while doing something violent.[18] She can also be described as docile, with her true nature hidden, as being slapped by someone would result in her not reacting or fighting back in her best interests, in most situations.[19] Her true nature can show in a hypothetical situation where if she had to kill people due to a life-threatening situation (eg, a bomb collar around her neck that would explode if she didn't kill people), she would be second in terms of being lethal.[20] According to Inkyu Basu, Ayano's "bloodlust" could even be detected while she was passing her in the school hallways, while Sakyu commented that their mother's energy could be felt in Ayano, like she had multiple layers, one of them being human, and one reminding Sakyu of her mother.[21]

While Ayano is cunning, she doesn't threaten people, as she doesn't want to arouse suspicion from others, believing that she is a murderer.[22] She doesn't want to be known; she tries to avoid gathering any kind of attention to herself, as she deliberately avoids other people and speaks only when necessary.[23] Ayano socializes just enough to not be considered a loner, but not too much to be well known by her classmates. Her "hobby" is trying to convince everyone around her that she is a normal girl with normal feelings. She understands expectations for a girl her age, and as such, she buys manga, plays video games, and rides a bike to project the image of a regular schoolgirl. However, she doesn't enjoy any of it and does it because she is expected to have "some degree of familiarity" with those things.[25][26][27] Ayano does study crime documentaries.[28] She learns to be a "normal girl" by eavesdropping at her school to learn what girls her age are doing or watching. If Ayano is asked about it, she can provide an answer and falsify her personality as a normal person who knows and enjoys the same things that other people her age know and enjoy.[29] In her free time, she is usually researching and learning about things and items that would trick people into thinking she is a normal girl.