Oka is the president of the school's occult club. She is completely convinced that ghosts, demons, and black magic really exist, and wants to dedicate her life to proving that these things are real. Oka is absent from school during the first three weeks of gameplay for mysterious reasons. As soon as she returns to school, she is immediately smitten by Senpai. Due to the fact that she falls for him in an extremely short span of time, she believes that there must be something supernatural about him, and begins studying him intently. She is an awkward girl who is regarded as "creepy" by the majority of the school, but she is actually quite harmless, and some people even find her to be endearing. Perhaps Senpai will think that there is something charming about her unusual nature...Oka has messy, shoulder-length dark navy-blue hair with a fringe hanging down the middle of her face, flowing across her right cheek. Her hair was less messy when she was a child. This was because her mother would comb her hair with love daily, and they cared for her well. When she grew older, she was responsible for her appearance, and her parents did not treat her like a child anymore. This is where her hair started to become messy and sloppy. Her eyes are light purple. She has large black rings around her eyes. Her lips and skin are pale, and the upper half of her face is slightly shadowed. In the future, Oka will have very pale skin. Her bust size is 1.05. YandereDev stated that she may be the shortest rival. Later on, Dev stated that her height is 159cm 5'2". Once re-added to the game, she will wear the default school uniform with light blue-gray thigh-high spiderweb stockings, light blue-gray spiderwebs, fingerless gloves, and black panties unless customized by the player. As the leader of the Occult Club, she will wear a black choker with a silver spider on it and the "Red Armband of Leadership" with an illustration of a black pentagram on her left arm.Oka walks very slowly, her hands clasped together and always looking shyly at the ground. Among the Personas that are currently implemented in the game, Oka will be Lovestruck. Before her removal, she was a Coward. If Oka saw a corpse, she would flee school and call the Police. If she witnessed a murder, she would start begging for Ayano Aishi to spare her life in exchange for her silence. She could not participate in physical fights against murderers. She would hide her face if Ayano aimed her phone at her. Oka is a stalker, but not a yandere, as she is too shy to harm others.[8] Her mannerisms are meant to make her look shy, timid and socially awkward.[9] She has been obsessed with anything paranormal since early childhood.Her self-confidence is extremely low, as in a hypothetical situation where Taro became interested in another girl, she would get really sad and give up on pursuing him. She watches creepypasta videos. Her favorite "creepypasta" is anything popular on the Japanese internet in the year that the game takes place.[13] Oka also played Corpse Party before. Additionally, even though she only uses the internet to watch videos, she likes to watch ghost hunter TV shows YandereDev says that she would enjoy watching media produced by Tim Burton. Oka's interest for the supernatural has even resulted in her secretly hoping for a zombie apocalypse to happen one day (as she has been wanting it her whole life), so that she could provide useful information in (almost) any situation.[17] Additionally, she has also attempted to summon these supernatural beings in her own room. She enjoys thinking about martial arts mainly because she fantasies about being a "combat exorcist", banishing evil spirits with a combination of martial arts and traditional exorcism techniques. Even though she is too shy and timid to do anything like that, she always enjoys daydreaming about it. She thinks it would be cool to combine physical combat skills with exorcism methods.

Oka Ruto:sitting in the middle of the Pentagram carpet