At the hospital where Toko was born, a baby born at the same time died in a medical accident. It was unclear which mother's child was the dead baby. Both mothers refused to test their blood, as they both wanted their child to die. Around the child's accidental death, it became clear that the two women slept with the same man.
Toko lived with one father and two mothers. Though the circumstances are a bit unclear, it's been confirmed that she was mistreated as a child. She was once locked into a closet and forced to stay there for three days without food. This traumatic experience resulted in her developing a pathological fear of the dark. She experienced severe psychological pressure and at some point turned to novels for comfort, but her negative feelings were too strong. This childhood trauma caused Genocide Jack to split off. Jack killed several young men; the people on the Internet, unaware of her gender, started to call her Genocide Jack. Toko blamed her mothers for Genocide Jack's creation.
On top of it all, Toko didn't have friends and was bullied in school. When she was in third grade, someone's lunch money was stolen and it was found in her desk. Toko was blamed for the theft, and her classmates tied her to the jungle gym with a garden hose.
Toko became extremely close to her pet stink bug, Kameko. She believed that Kameko was a special insect that could understand her feelings.
Toko's first love was a boy who she had been friends with in elementary school. When she found out he was moving away to Shikoku, she realized that she was indeed in love with him. Being too shy to tell him in person, she instead wrote him a letter. The next day, Toko found that the boy had pinned her letter on the bulletin board as a way of mocking her. Genocide Jack reacted by following the boy to Shikoku and killing him.
In Toko's eighth grade year, a boy from the neighboring class asked her out on a date completely out of the blue. She then spent three days and three nights planning the date. Toko eventually decided to go see an action movie. Halfway through it, her date disappeared. She later discovered that the boy had only asked her out because he'd lost a bet with his friends, causing her great emotional trauma.
However, the letter Toko wrote for her first love was read by her teacher. The teacher told her she had a way with words, which started Toko's career as a writer. One of her romance novels, 'So Lingers the Ocean', was a huge hit that managed to shoot fishermen to the top of all the "Hottest Men" polls. Despite her young age, Toko won several awards and was constantly on the top-selling list.
Toko used to attend Riverbank Girl's High School and was later invited to Hope's Peak Academy's 78th class as the Ultimate Writing Prodigy.
