Saori is shown to be very anti-social and seemingly cold to even her closest friends, often ignoring them or saying hurtful things. But this is, in fact, a façade, as she is actually caring towards her friends. However, due to an incident before middle school, it caused her to become distant and hateful. She is in fact very protective of Shuichi, and is affected by many things surrounding him, evident by the fact that she stopped going to school upon hearing Shuichi is dating Anna Suehiro.
Saori was one of the original people who saw the potential of how cute Shuuichi is dressing up as a girl, and often encouraged him to do so. As such, she is accepting of this and wants him to continue as long as he desires to.
She is first introduced as friends of Yoshino Takatsuki & Nitori Shuuichi, but due to a falling out before middleschool, it has caused the friends to become distant towards each other, with Saori becoming hateful towards Yoshino. This becomes clear when someone in the class teases Shuuichi about having dated Yoshino the year before, which Saori proceeds to hit the person over the head with a book, and promptly leaves the classroom.
It is later shown that the reason they had a falling out was because Saori confessed her love towards Shuuichi, which he turned her down, she then finds out that Shuuichi had earlier confessed his love for Yoshino, which she turned him down. This causes a rift between the friends, Saori stating that she hates Yoshino, which in turn causes Yoshino to say that she, in fact, hates Saori because of her victim mentality.
Kanako Sasa becomes the mediator mainly between Yoshino and Saori, trying to get them to forgive and forget the past, but to no avail. Throughout the story Yoshino and Saori begin to mend their old wounds, especially when it is revealed that Shuuichi and Anna Suehiro are dating, which crushes Saori, causing her to abandon school. Yoshino brings her homework to her and tries to rally her to keep going to school and to not let such things ruin her future.
Eventually Saori is able to forgive Yoshino and responds to Yoshino's comment on "everyone being special" feeling that there is no meaning in saying everyone is special, but she says that, just because that is just the way she is.