Manga Series
- ALL OUT!!
- Always 3 chome no Yuhi
- Obey Me!
- Occultic;Nine
- OCTOPATH TRAVELER
- on BLUE Series
- OPERA Series
- orange
- Over Drive
- OZMAFIA!!
- [Oshi no ko]
- Oishii Coffee no Irekata
- Okami Kakushi
- Ookami kodomo no Ame to Yuki (Wolf Children)
- Okiku Furikabutte
- Okasan to Issho
- Treat of Reincarnation
- Okusama ga Seito Kaicho!
- Okoshiyasu Chitose Chan
- Touch Detective Mushroom Garden
- Please Tell Me! Galko-chan
- Ojiisan Sensei
- Ojisan to Marshmallow
- Ojisan Ha Kawai I Mono Ga Osuki.
- Ojarumaru
- Osen
- Osomatsu-san
- Ochikobore Fruits Tarte
- Ossan's Love
- Odekake Kozame
- Otogi Jushi Akazukin
- Otona no Boguya-san
- A Galaxy Next Door
- Otome Yokai Zakuro
- Onegai Twins
- Onegai Teacher (Please Teacher!)
- Onegai My Melody
- Opanchu Usagi
- Ohisama
- Omamori Himari
- Omiyasan
- Only Yesterday
- Oyasumi Punpun
- Ontama!
- Onichan Dakedo Ai Sae Areba Kankeinaiyone
- Oni-Chan no Koto Nanka Zenzen Sukijanaindakarane!!
- Onimai: I'm Now Your Sister!
- Omae wa mada Gunma wo shiranai
- Otenki Sentai How Weather
- Oneechan ga Kita
- A Girl & Her Guard Dog
- Omukaedesu.
- Osake wa Fufu ni Nattekara
- Okane ga Nai!
- The Angel Next Door Spoils Me Rotten
- Okami San Ha Taberaretai
- Ookami-san Series
- Okami Shojo to Kuro Oji
- Octave
- Ozuma
- The Diary of Ochibi-san
- Odd Taxi
- Otoca Doll
- Orient
- Orix Buffaloes
- Olympia Cuculus
- Alternative Girls
- Hortensia Saga
- Orenchi no Furo Jijyo
- On Air Dekinai!
- Onnamichi
- Online Game
- Ooi! Tombo
- Overman King-Gainer
- Overlord
- Omo ni Naiteimasu
- Otome wa Boku ni Koishiteru
- My Next Life as a Villainess: All Routes Lead to Doom!
- Trapped in a Dating Sim: The World of Otome Games is Tough for Mobs
- Otoyome Gatari
- Otokomeshi
- Ore, Tsushima
- Ore, Twintail ni Narimasu.
- Shomin Sample
- Ore Ga Sukina No Ha Imotodakedo Imoto Janai
- Oretachin ni Tsubasa wa Nai
- Oretachi Majikou Destroy
- Solo Leveling
- Special training in the Secret Dungeon
- Ore no Imoto ga Kon nani Kawaii wake ga nai
- Ore no Kanojo to Osananajimi ga Shuraba Sugiru
- Ore no Sora Series
- Ore no nonai sentakushi ga gakuen Love comedy wo Zenryoku de Jyama Shiteiru
- Ore o Suki nano wa Omae dake kayo
- Ore monogatari!!
- Okami San Ha Taberaretai
- Oh-oku ( Danjo Gyakuten)
- Ooya-san wa Shishunki !
- Ohoka Echizen
- Oedo Rocket