Ticci Toby

Ticci-Toby (Tobias Erin "Toby" Rogers) is a creepypasta character and Slenderman's confidant.

Key features:

Appearance: Pale skin, tousled brown hair, dark eyes; usually wearing a white T-shirt and sweatpants.
Mental disorders:
congenital insensitivity to pain with anhidrosis;
schizophrenia;
Tourette syndrome (multiple motor tics);
PTSD (after a car accident);
amnesia (after meeting Slenderman);
ADHD;
depression.
Character: hyperactivity, sudden mood swings (from emotional elation to anger), sarcasm, mental instability; capable of kindness to certain people.
Brief biography:

Born with multiple mental disorders, he was homeschooled because of it.
I lost my older sister, Lira, in a car accident, which left me with serious psychological trauma.
He was abused by his father (who was a drug addict and prone to violence).
In a state of mental breakdown, he killed his father, set fire to the house and fled.
He was found by Slenderman and became one of his confidants, losing his memories of his past life.
Behavioral features:

tics and uncontrolled movements due to Tourette syndrome;
insensitivity to pain;
episodic memory lapses;
a tendency to destructive actions (for example, biting the skin on the hands).