Yamagishi Yukako presents herself as a phlegmatic teenager with an aloof bearing. After being expelled from one of the few junior high schools in her city 3 years ago, she chose to continue her education in Morioh, a neighboring town.
At Budogaoka Middle & High School, she's amassed many popularity points for her nonconformity. Her graceful stride, paired with her reputation, makes it difficult for schoolmates to talk to her.Contrary to assumption, Yukako's wayward tendencies and behavior does not clash with her academic success or responsibilities. She stays on top of her studies and is a hard worker, proving that she isn't a run-of-the-mill troublemaker wanting attention. Her delinquency (beyond the series-typical violence...), includes breaking curfew, trespassing, disregarding authority figures, and committing petty theft against salaried workers and corporations. She doesn't steal out of necessity: only because she's bored.In 1991, Yukako was diagnosed with borderline personality disorder and anxiety, and was noted to "daydream". She has most recently developed PTSD following ..Nijimura Keicho.. shooting
her with the Stand-granting bow and arrow during the early days of February 1999.Despite having a firm sense of justice, Yukako personally feels little obligation to follow the law and will break them to further her goals.Her strong will— that is tightly bound to her mild-temper, is used to protect her loved ones, the helpless and, most importantly, herself. While asserting that she has enough on her plate with keeping herself safe and, Yukako will often go out of her way to help even those she has little to no connection with. Her unapproachable demeanor is a veneer that hides a kind, selfless girl that fights tirelessly for any idea she believes in.As a martial artist, the exercises she's learned from Taekwondo and Byakuren Kaikan are used at their most efficient forms for the quickest result. Her fighting expertise is further rounded by her training in bōjutsu, even having her own collapsible bō made of steel.Yukako carries an unnatural ruthlessness to achieving her goals, a phenomenon known as dark determination
that fills her violet eyes with a dark flame. At this point, she's able to set aside her sense of morality to kill someone in cold blood.She retreats in her mind to cope, where nothing can hurt her.Terrified of the thought of being the next missing, dead, or assaulted girl on the news, Yukako signed herself up for martial arts classes during 1995 and has since become a star pupil. She thought herself to be as close to untouchable as humanly possible; that is, until she was incapacitated in a residential area of Morioh after a golden arrow pierced her through the heart. Surviving the blow, Yukako was thrusted into a bizarre world at the price of bruising her ego and mind.Besides honing her ability into a strategic force, Yukako, at the start of her journey as a Stand user, wanted to find the one who gave her a Stand. She later learned that ..Nijimura Keicho.. was murdered well before she could find him, much to her disappointment and dismay. With the only alternative being to stay stuck on something she couldn't change, Yukako eventually accepts his death and mourns what will never be said between them.