Yuri is portrayed throughout the majority of the game as being shy, generous, polite, apologetic, very intelligent, mature, eloquent, and passionate about topics she is interested in, although she is also very insecure, awkward, and has a tendency to act slightly condescending and patronizing to mask her self-doubt. Her facade of passivity and level-headed nature occasionally breaks, however, as Yuri does argue passionately and aggressively with Natsuki over their differing opinions on writing styles. Yuri has a deep desire to be liked by others and is afraid to speak her mind on matters as she believes it will make her seem unlikable. Due to her social ineptitude, she can be innocently insensitive, but once she realizes what she said could be considered rude, she almost immediately apologizes, repeatedly saying she did not mean it. As stated by the protagonist, Yuri likes to think before she says something.

Yuri is the "shrinking violet" (a term to describe a character who prefers to blend in with the scenery than to attract unwanted attention) or "dandere" of the club members because of her constant apologetic nature. The attribution is also because of being shy to discussions beyond her category of interest, her interests being literature, horror, and general surrealism, which she examines and articulates expertly and encourages others to follow as well. In the middle of Act 1, Natsuki and Yuri getting into a debate about their different writing styles. Choosing to side with Natsuki will cause Yuri to shy away from the player, and if the protagonist attempts to read their poem to Yuri, she will not respond, which will cause the protagonist to decide it is best to leave her alone. If the player calls for Sayori to diffuse the situation, Sayori will compliment both Yuri and Natsuki on their writing and capabilities. The argument will dissolve afterwards and both Yuri and Natsuki will be satisfied with Sayori's response.

Yuri's love of surrealism seems to be foreshadowing further events of the game, with Yuri's surrealistic eyes and the game's horrific nature after Sayori's suicide. Yuri prefers poetry that uses metaphorical symbolism and enjoys collecting unusual ornate knives, implicitly (in Act 1 at least) used for self-harm. The detailed summaries of the Portrait of Markov novel in the first and second act, when also taking the scattered dialogue references into account, all end up tracing back to her unstable nature and unhinged personality.

During Act 2, Monika amplifies Yuri's negative personality traits. This causes her to have sanity slippages that result in an abnormal obsession with the protagonist and her already-existing hobbies becoming more of perverted detailing and self-destruction, to the point where Monika suggests that Yuri cuts herself due to a fetish. This also causes her to become invasive and condescending to the other club members, asking Natsuki "Why don't you look for coins under the vending machine?", which causes Natsuki to cry and run away. In one occasion, Yuri shows a poem to the protagonist with blood and urine stains on it, telling him that she has put her scent on it. Yuri will then realize what she has done and leave the club, stating that she is going to vomit.

Yuri recognizes that something is wrong with her and that her comments and behavior are inappropriate, enough so to feel something bad will happen despite her happiness. She is ultimately unable to control her obsessive outbursts. It reaches a point where, after she confesses her love to the protagonist, she stabs herself to death out of over-excitement or rejection (depending on the protagonist's response to her confession, both lead to the same outcome, courtesy of Monika). Yuri's body is left decomposing for three days, and is then discovered by Natsuki, who immediately vomits and runs away. When she is discovered by Monika, both Yuri and Natsuki's files are deleted, leading to Act 3.