Mac - Addiction and Obsessive Love Disorder
Bloo (after the first 3 episodes of the show in Season 1) - Narcissistic Personality Disorder (Somatic Narcissism)
Terrence - Narcissistic Personality Disorder (Overt Narcissism/Classic Narcissism)
Mr. Herriman - Obsessive Compulsive Personality Disorder and Cynophobia
Frankie Foster - Intermittent Explosive Disorder
Wilt - PTSD
Coco - Object Sexuality
Eduardo - Dependent Personality Disorder, Social Anxiety Disorder, and Arachnophobia
Duchess - Narcissistic Personality Disorder (Somatic Narcissism)
Bendy - Narcissistic Personality Disorder (Covert Narcissism) or Antisocial Personality Disorder (Sociopathy)
Benjamin Edward Factor III - Antisocial Personality Disorder (Sociopathy)
Berry - Borderline Personality Disorder (Petulant Borderline)
Cheese - Autism Spectrum Disorder (Level 1 Autism/Asperger's Syndrome), ADHD, Obsessive Compulsive Disorder, Gingivitis, Trypophobia, and Arachnophobia
Chris - Obsessive Love Disorder
Dylan Mitzak - Narcissistic Personality Disorder (Covert Narcissism)
Erin Peterson - Narcissistic Personality Disorder (Somatic Narcissism)
Goo - ADHD
Goofball John McGee - Binge Eating Disorder
Kip Snip - Narcissistic Personality Disorder (Somatic Narcissism)
Louise - Autism Spectrum Disorder (Level 1 Autism/Asperger's Syndrome)
Nemesis - Narcissistic Personality Disorder (Malignant Narcissism) and Intermittent Explosive Disorder
Prince Charming - Obsessive Love Disorder
Red - Down Syndrome
Sally - Borderline Personality Disorder (Petulant Borderline)
Sassyfrass - Histrionic Personality Disorder or Narcissistic Personality Disorder (Seductive Narcissism) and Obsessive Complaining Disorder
Sloppy Moe - Trimethylaminuria
Snooty Girl - Spoiled Child Syndrome
Mojo Jojo - Narcissistic Personality Disorder (Cerebral Narcissism/Malignant Narcissism) and Intermittent Explosive Disorder