- Onipan!
- Noiseman Sound Insect
- Onmyo Kaiten Re:Birth Verse
- The Chronicle of the Big Battle between Yin and Yang
- Onmyouji
- Hakone-chan
- Onyankopon
- Hey! Tonbo
- Tonbo! Season 2
- Wolf Children
- Wolf Girl & Black Prince
- Spice and Wolf
- Spice and Wolf II
- Spice and Wolf II Specials
- Spice and Wolf II: OVA
- Spice and Wolf: Merchant Meets the Wise Wolf
- Okami-San and Her Seven Companions
- The Big First-Grader and the Small Second-Grader
- Big Windup!
- Big Windup!
- Big Windup! 2
- Big Windup! 2 Special
- Science SARU x MBS Original Short Anime Daisakusen!
- Oomuro-ke: Dear Sisters
- Oomuro-ke: Dear Friends
- Ōoku: The Inner Chambers
- Ooya-san wa Shishunki!
- Kaina of the Great Snow Sea
- Kaina of the Great Snow Sea: Star Sage
- Opus.COLORs
- Orange
- Orange: Mirai
- The Hidden Dungeon Only I Can Enter
- Solo Leveling
- Solo Leveling Season 2: Arise from the Shadow
- Solo Leveling: ReAwakening
- Solo Leveling: Specials
- Shomin Sample
- Ore ga Ojousama Gakkou ni "Shomin Sample" Toshite Gets♥Sareta Ken Specials
- My Sister, My Writer
- Ore ga Suki nano wa Imouto dakedo Imouto ja Nai Specials
- My Love Story!!
- My Little Sister Can't Be This Cute
- My Little Sister Can't Be This Cute: Specials
- My Little Sister Can't Be This Cute 2
- My Little Sister Can't Be This Cute 2 Specials
- Oreshura
- My Mental Choices Are Completely Interfering With My School Romantic Comedy
- Ore no Nounai Sentakushi ga, Gakuen Love Comedy wo Zenryoku de Jama Shiteiru OVA
- Ore no Sora Keiji-hen
- I'm the Evil Lord of an Intergalactic Empire!
- I Parry Everything
- ORESUKI Are you the only one who loves me?
- Ore wo Suki nano wa Omae dake ka yo: Oretachi no Game Set
- I, Tsushima
- I, Tsushima (ONA)
- Gonna be the Twin-Tail!!
- Oreca Battle
- Orenchi no Furo Jijou
- ORESUKI Are you the only one who loves me: Game Over
- We Without Wings – Under the Innocent Sky
- Orient
- Orient Part 2
- The Foolish Angel Dances with the Devil
- Fish in the Trap
- Love is Like a Cocktail
- Osake wa Fuufu ni Natte kara: Yuzu Atsukan
- Osamake: Romcom Where The Childhood Friend Won't Lose!
- You Can't Be In a Rom-Com with Your Childhood Friends!
- If My Favorite Pop Idol Made It to the Budokan, I Would Die
- My Star: Season 2
- My Star: Specials
- Oshiete Mahou no Pendulum: Rilu Rilu Fairilu
- Please tell me! Galko-chan
- Please tell me! Galko-chan OVA
- Osomatsu-kun (1988)
- Mr. Osomatsu
- Mr. Osomatsu 2
- Osomatsu-san 3rd Season
- Mr. Osomatsu 4
- Mr. Osomatsu the Movie
- Go!! Karate Club
- Otaku no Seiza
- Otaku no Video
- Weather Report Girl
- Fairy Musketeers
- Angel Tales
- Angel Tales
- Otogi Zoshi: The Legend of Magatama
- Princess Connection
- My Next Life as a Villainess: All Routes Lead to Doom!
- Hamefura Movie
- Otome Game no Hametsu Flag shika Nai Akuyaku Reijou ni Tensei shiteshimatta... OVA
- My Next Life as a Villainess: All Routes Lead to Doom! 2nd Season
- Trapped in a Dating Sim: The World of Otome Games is Tough for Mobs
- Zakuro
- Otome Youkai Zakuro Picture Drama
- Armor Shop for Ladies & Gentlemen
- Otona no Bouguya-san 2nd Season
- A Galaxy Next Door
- The Angel Next Door Spoils Me Rotten
- Jing: King of Bandits
- Golden Warrior: The Gold Lightan
- The Brave of Gold Goldran
- Ouran High School Host Club
- Royal Space Force: The Wings of Honneamise
- King's Game
- Ranking of Kings
- Ranking of Kings: The Treasure Chest of Courage
- The Royal Tutor
- The Royal Tutor Movie
- Outbreak Company
- Outlanders
- Oval x Over
- Over Drive
- Overflow (TV ver.)
- Overflow (Uncensored)
- Overlord
- Overlord II
- Overlord III
- Overlord IV
- Overlord Movie 1: The Undead King
- Overlord Movie 2: The Dark Hero
- Overlord: The Sacred Kingdom
- Overlord: Ple Ple Pleiades
- Overlord: Ple Ple Pleiades - Clementine Toubou-hen
- Overlord: Ple Ple Pleiades 2
- Overlord: Ple Ple Pleiades 3
- Overlord: Ple Ple Pleiades 4
- Overman King Gainer
- Overtake!
- Seraph of the Endless
- Seraph of the Endless
- Seraph of the End: Vampire Reign
- Owari no Seraph: Vampire Shahar
- Seraph of the End: Battle in Nagoya
