Toby wasn't always a normal kid. He grew up with many different mental disorders, making it hard for him to fit in with the 'normal crowd', along with a disease that attacked his nervous system, causing him to be completely numb to pain, and an extreme case of Tourette's syndrome. Which causes Toby to make uncontrollable jerks, 'tics', and other abrupt movements, and is most recognized for cracking his neck uncontrollably. Earning him the demeaning nickname 'Ticci-Toby' from his peers. Toby used to attend public school up until the point he could no longer handle the severe teasing and bullying, and so he was then transferred to homeschooling early on.
He grew up with little - to almost no friends. He lived with his mother, his older sister, Lyra, and his father who later lost himself to drugs, alcohol, and gambling and became abusive towards his family. When Toby was 17 years old his sister and he were involved in a tragic car accident, resulting in Lyra's death. After that Toby grew even more troubled, his symptoms worsening, barely eating, not leaving his bedroom, and growing less and less social. He began to lose some fragments of memory, start seeing hallucinations of his sister's twisted and mutilated corpse, and see a strange figure, standing outside of his bedroom window at night. He would take out his stress and anxiety by chewing the flesh from his fingers. His mother was worried about the state Toby was in and had decided to get into contact with a psychiatrist to help with, but it didn't work.
Toby soon lost all control of his sanity and one night attacked and killed his father, and then fled out of the house. Grabbing two of the hatchets from his father's garage, a box of matches, and a gallon of gasoline, he proceeded to set the neighborhood on fire in an attempt to escape from the police. The fire surrounded him and as he was about to give in to his own death, Slenderman appeared and saved him before he blacked out. When Toby woke up, he has no recollection of what happened and all of his memories of his previous life are erased.
Approximately two weeks later, after Toby's disappearance, Toby's mother listens to a news story about the murders of several teenagers. The main suspect is Toby due to one of his hatchet's being found at the crime scene. This marks the moment Toby had officially become one of the Slender Man's Proxies.