Shatter has black hair that covers his right eye. He has pale skin and his eye color is light teal. In his first appearance he wears a maroon hoodie.
Shatter is a shy gay. He doesn't seem to be very confident about himself, lacking the resolve he needed to tell his childhood friend about his feelings. Because of an accident he doesn't like parks, though he doesn't muster the strength to try and convince them to do something else.
He accurately remembers what Sophie used to wear. Whether that's because he's good at remembering things or is so traumatized by the happenings that they have burned themselves into his memory is unknown.
A week after Shatter's eighth birthday, he and his childhood friend Sophie went to a park without parental supervision. They played with a red "kush ball" that she had gifted him.
While playing, Shatter throws the ball too far and it lands on the street. Unaware of her surroundings, Sophie goes to get the ball, when she is hit by a car. The ambulance doesn't make it in time and she dies bleeding in Shatter's arms.
Sophie is Shatter's childhood friend with whom he used to play with. Shatter is described as to having romantic feelings for Sophie, although Sophie's feelings are undisclosed to everyone but the author.
The two only boys in the group are dating and randomly make out during Masahiko's torture, despite Shatter being very embarrassed about it in the aftermath. They met in the mental hospital where Yami decided to stay another month despite being able to leave already, just so he could spend time with his boyfriend. Later, however, Yami breaks up with, and Shatter falls into despair about it, being reminded of his childhood friend.
She ships Shatter with his boyfriend Yami and gets pretty excited when talking about the relationship the two boys have.