As little girls, Kanna often bullied Haruka. Deep down she wished to befriend her and Yuuya but grew envious after he defended Haruka from her. Eventually she was able to befriend them and Sayuri though, after another bully began to pick on all of them and facing a terrible dog attack not too long after.
With the girls separated, Kanna being a first year in Middle School now, they got back together after finding out Yuuya had feelings for a classmate. Angered and concerned, they got together to meet up with him and the girl before he could confess his feelings. They pointed out their plans to get rid of the girl, with Kanna agreeing to what Sayuri and Haruka told Yuuya after he started to doubt they were serious.
As they made threats, Yuuya attempted to get the girl to safety until a train car collided with him. While recovering the memories slowly became vague in everyone's minds and the girl transferred to a new school, with Yuuya trying to determine if he was saved or pushed.
Kanna is the only girl unable to come up with an idea at first and suggests they take the time to think it over and wait. The following evening Kanna has a conversation with Yuuya and promises to think of an idea they can use after they watch a news report on the sudden popularity of Mascot Characters. She is inspired by this and suggests a Mascot Cafe, which goes over well with the other girls.
As the next few days go by they work on the details of the Mascot and make the outfit.
A few days later, Kanna comes to Yuuya's house to discuss their plans, but this is cut short when an envious Haruka pays Yuuya a visit and the girls get into an arguement.
Eventually, with all their efforts paying off the group celebrates the email Yuuya got, inviting them to a Ceremony to celebrate their hard work. However, Kanna isn't there at school that day and they inform Yuuya that she is sick. He makes plans to pay her a visit out of concern, but when they get delayed he sadly heads for home, annoyed that he was unable to see her. To his surprise, Kanna gives him a call instead. He expresses relief and requests visiting her in the morning, but not before Kanna leaves him with a cryptic comment.
When the Ceremony approaches Kayako is found murdered. To deal with stress from the ordeal Yuuya takes to locking himself within his room for a few days and returns to school- shocked to find out his friends are happy she is out of the way. He approaches Kanna, concerned over Haruka and Sayuri, but when she sees nothing suspicious about it he decides to put space between himself and the girls.