Osmerelda / Esmerelda Kim (12 episodes, 2014-2021)
Omar (8 episodes, 2020-2021)
Orla (7 episodes, 2020-2021)
Oswald (7 episodes, 2020-2021)
Little O / Orpita (7 episodes, 2021)
Ms. O / The Big O (4 episodes, 2020-2021)
Agent Orchid (4 episodes, 2014-2021)
Opal (3 episodes, 2020-2021)
The Shadow / Olizabeth (3 episodes, 2020-2021)
Oona (3 episodes, 2020-2021)
Brutus / Brutas (3 episodes, 2020-2021)
Van Computer / Van computer (3 episodes, 2020-2021)
Star Wipe (3 episodes, 2021)
Orana (2 episodes, 2020-2021)
Oliver (2 episodes, 2020-2021)
Monsieur Papier Mache (2 episodes, 2020-2021)
Lady Beard / Lady Bread (2 episodes, 2020-2021)
Olympia (2 episodes, 2021)
Freeze Ray Ray (2 episodes, 2020-2021)
Otto (2 episodes, 2021)
Otis (2 episodes, 2021)
Jamie Jam (2 episodes, 2020-2021)
Shelly Catessan / Shelly Catessen (2 episodes, 2020)
Yelling Club Member (2 episodes, 2021)
Olando (2 episodes, 2021)
Kid Computer Agent (1 episode, 2020)
Swamp Creature (1 episode, 2021)
Amish Patel (1 episode, 2021)
Dream Weaver (1 episode, 2021)
Tourist (1 episode, 2021)
Oppola (1 episode)
Clockie the Snowman (1 episode, 2021)
Chloé the French Bride 2 (1 episode, 2021)
Dream Scientist (1 episode, 2021)
Debra / Donna (1 episode, 2020)
Squirmy the Mermaid (1 episode, 2021)
Sister Sally #1 (1 episode, 2020)
Goo Wife (1 episode, 2020)
Hot Dog Vendor (1 episode, 2021)
Sound operator (1 episode)
Star Wipe (1 episode, 2021)
Oscar (1 episode)
Kid Mechanic (1 episode, 2020)
Ozzy (1 episode, 2021)
Optometrist (1 episode, 2020)
Mr. Lightning (1 episode, 2021)
OS Professor (1 episode, 2021)
Magnet Maggie (1 episode, 2021)
William Ocean (1 episode, 2021)
Confetti Betty (1 episode, 2021)
Crazy Eights (1 episode, 2020)
Agent Ono / Kid Guard (1 episode, 2020)
Tessa Twosie (1 episode, 2020)
Mr. Unpredictable (1 episode, 2020)
Oracle (1 episode, 2020)
Dr. Dry (1 episode, 2020)
Caveman (1 episode, 2020)
Happy Go Lucky Agent (1 episode, 2020)
Reporter (1 episode, 2020)
Wheelie Dan (1 episode, 2020)
Agent (1 episode, 2020)
The Utensiler's Younger Sister (1 episode, 2020)
Ancient Ms. O (1 episode, 2020)
Eve (1 episode, 2020)
Xeno (1 episode, 2020)
Olive (1 episode, 2021)
Lady With Thundercloud (1 episode, 2021)
Seahorse Tanya (1 episode, 2021)
Sasha Sanderson (1 episode, 2021)
Reporter #1 (1 episode, 2021)
Singing Telegram Sarah (1 episode, 2021)
Professional Cyclist (1 episode, 2021)
Reporter-Ville Reporter #4 (1 episode, 2021)
Reporterville Reporter #2 (1 episode, 2021)
Seattle Dr. O (1 episode, 2021)
Newsie Norman (1 episode, 2021)
Singapore Devil Sticks Busker (1 episode, 2021)
Odd-Ska-Teer 3 (1 episode, 2021)
Marty Marmalade (1 episode, 2021)
French Bride (1 episode, 2021)
Security Agent (1 episode, 2021)
Osemite (1 episode, 2022)
Xanthia (1 episode, 2022)
Evil Scarecrow (1 episode)
Cardboard Carl (1 episode)
Logan the ogre (1 episode)
Agent Occidental (1 episode)
Manila Ms. O (1 episode)
Ms. O DBL (Circa S1) (1 episode)
Yodeling Pretzels (1 episode)
Alien aerobics class member (1 episode)
Student (uncredited) (1 episode, 2020)