Kaori Shirasaki/Chronology

History
Kaori was admired by everyone in school. She met Shizuku Yaegashi in elementary school becoming the only person that would talk to her, which gradually led to the two of them becoming best friends.

She admired Hajime Nagumo for his strong will after witnessing an incident in middle school when he stood up to a group of delinquents that were harassing a child and his grandmother. She wanted to get to know him better after the incident and would spend the next year waiting outside the school Hajime was attending in the hopes that she would be able to meet him. Unfortunately for her, Hajime was always gone by the time Kaori arrived at his school.

During her first year of high school, Kaori discovered that Hajime would be in her class after she saw him sleeping during their orientation. She would constantly talk with him in order to get to know him better. During one occasion, in her attempts to better understand Hajime's interests, when she was exploring Akihabara with Shizuku, she asked a store clerk to buy an a certain adult game because the regular version was sold out. In an attempt to obtain it, Kaori claimed that she was planning to buy it for her father (shocking everyone in the store).

She didn't realize she was in love with Hajime until he fell into the abyss.

After that incident, she believed that Hajime was still alive and trained herself to be stronger.

Along her journey in the Great Orcus Labyrinth, they were cornered by a woman of the demon race named Cattleya. She and the others were saved by Hajime but as a completely changed person. After the battle, Yue noticed Kaori's stare at Hajime and then told her: "Is that the extent of your feelings?". Later after some time during their talk she then saw Hajime get mad at some rogue mercenaries when they disrespected Shea by calling her a slave, which leads to Hajime beating them up. She then realized that he was still the same person she loves, so she confessed to him and told him that she wanted to follow him and declaring at the same time that she wouldn't yield to Yue.

She died from the attacks of Daisuke Hiyama's hand later on, but she was resurrected and requested that her soul to be transferred into the body of the recently deceased apostle Noint. While using Noint's body, Kaori's original body was stored in Hajime's Treasure Trove while being frozen by Yue's magic to preserve it. After returning to Earth, Kaori gained the ability to switch between her normal form and her apostle form, thanks to Yue's ability to create apostles after she was freed from Ehit's possession, where she gained silver hair and wings.