Kayo Hinazuki is Satoru Fujinuma's primary school classmate and one of the victims of the serial kidnapping case 18 years ago. She was a loner due to her mysterious family life, which made her an easy target to kidnap. In an attempt to prevent her kidnapping, Satoru desperately tries to befriend her.
Kayo doesn't have much of a presence in class. Prior to becoming friends with Satoru's group, she didn't have any friends and didn't speak to anyone. She considered Satoru and herself as 'Fakes'. Kayo doesn't open up to many people because of her mother's abusive nature.
Kayo's mother, abused her quite a lot throughout her life. Many injuries included suffocation, bruises and other tortures. When Kayo first met Satoru during the 18 year "Revival" she asked Satoru to kill someone for her (meaning it as a' joke'), however, she had actually wanted him to kill her mother, out of her depression from the abuse her mother gave her.
After Satoru wakes up, She visits him with her son. She reflects on her discomfort of leaving him behind and is chided by Satoru in turn.
|“||Are you stupid? (JP: Baka na no?)||„|
|“||Everybody is fake, living in their fake lives.||„|
|~ Kayo to Satoru|
|“||Can you kill someone for my sake?||„|
|~ Kayo to Satoru|
|“||When I get bigger, big enough to go somewhere by myself, I want to go to a land that’s far away. I want to go to a faraway island. I want to go to an island that has no people. I want to go to an island that has no pain or sadness. On that island, I can climb a tree when I want to climb, swim in the sea when I want to swim, and sleep when I want to sleep. When I think about the town without me, I feel a sense of relief.I want to go far, far away.||„|
|~ Kayo's poem; The Town Without Me|
- Kayo always use the phrase "Are you stupid?" when talking to Satoru. This phrase is also used by Airi Katagiri, which gives him a shock when he hears that, giving a hint that Airi is likely a reincarnation of Kayo for him.
- In the manga version, Kayo is not transferred to a new school after the incident but in the anime version, she did. It creates a little confusion in the end as Kayo marries Hiromi which is has a slight chance to happen due to this.