|Appearance||Period 5: Bloody Valentine|
Sasaoka is described as cute and pretty by other characters. She has long light-colored hair that frames her face, and her big eyes appear cold and unfeeling. She attends an Academy and wears a uniform.
Sasaoka appeared to be an angry and quiet girl who spent most of her time glaring or observing Misaki. After being pushed enough, she finally snaps at Misaki, physically threatening her to stay away from Naoyuki and telling her off.
Sasaoka first appeared staring at Misaki from an area opposite of the window she had been standing by. She glared at her, startling Misaki until she got distracted by her friend and turned away.
The following day Misaki approached Naoyuki to give him the chocolate she spent so much time making when she overheard him speaking with a friend. He mentioned how he had been a bit distant with the girl lately due to her being harassed; and he was hoping to make her feel better by making Valentines Day special- but as Misaki realized what he had been saying, Sasaoka grabbed her and forced her outside to chat. She threatened Misaki and started yelling at her until Naoyuki showed up, telling her not to waste her time. She coldly tells Misaki that she is being delusional, as he was never dating her and he rejected her feelings.
This causes Misaki to remember the event as it actually happened, ending with him going on to meet with Sasaoka. This had caused her to lash out at them, breaking a window to injure Sasaoka, and making the threatening letters and sending one to her. Naoyuki pretended to break up with Sasaoka to make Misaki go away in order to keep her safe- but pushed to her limit, the broken Misaki responded by attacking them with a large rock, leaving them on the ground unconcious and bloody until the ambulance arrived.
It's later revealed that Misaki managed to get away from punishment by framing Sasaoka, and she has since been institutionalized.