O
Ocean Waves
(Umi ga Kikoeru)
- Anime Cubed Images: I Can Hear the Sea
- Anime-Planet - Ocean Waves
- Nausicaa.Net: Ocean Waves
- Umi Ga Kikoeru
- Wada-kun's Umi ga Kikoeru Page
Okyu no Trinity
Olympos
One Piece
- a bene placito
- Ao Umi Monogatari (Japanese)
- a pirate's life for me
- Anime Cubed Images: One Piece
- Anime-Planet - One Piece
- Anime Yume - One Piece
- Assurance: Usopp and Vinsmoke Sanji Fansite
- Challenge Life
- Codename: Prince - A shrine to Sanji from One Piece!
- COMMON SUN (Japanese)
- Diamond in the Desert
- Fahrenheit451
- Freedom to Choose
- Hopelessly Devoted
- Ikou!
- Inherited Will
- Minitokyo - One Piece Wallpapers and Scans
- Mr. Prince
- Official Manga Site (Japanese)
- Official Website (Japanese)
- One Piece Coloring Pages (Italian)
- OnePiece.de (German)
- One Piece fan site (Japanese)
- OnePiece.it (Italian)
- ONEP.jp (Japanese)
- One Piece Manga Forums (French)
- One Piece Route Search (Japanese)
- One Piece Wiki
- One Piece World (Italian)
- OPLuffy (French)
- OPM (French)
- OPwiki (German)
- Paragon
- PIRATE ALLIANCE
- Professional Pirate Thief
- Promise: Usopp and Kaya Fansite
- Romance Dawn
- ROYAL BEAUTY: Nefertari Vivi
- Strawhat: Fanpage de One Piece (French)
- the HERO never dies
- theOtaku - One Piece Portal
- There's no a King without his Queen
- Trafalgar D. Law Fanlisting
- True Marine
- VIZ - One Piece
One-Punch Man
- Anime-Planet - One-Punch Man
- Average Hero
- Cyborg Prince
- Minitokyo - Onepunch-Man Wallpapers and Scans
- Ninja Princess
- Official Manga Site (Japanese)
- Official Anime Site (Japanese)
- One-Punch Man Wiki
- Original Webcomic Site (Japanese)
- theOtaku - One-Punch Man Portal
- VIZ - One-Punch Man
One Week Friends
(Isshuukan Friends)
- Anime-Planet - One Week Friends
- Isshuukan Friends Wiki
- Minitokyo - Isshuukan Friends Wallpapers and Scans
- Official Manga Site (Japanese)
- Official Site (Japanese)
- There's Nothing I Want to Forget
Only the Ring Finger Knows
(Sono Yubi Dake ga Shitteiru)
- Anime Cubed Images: Only the Ring Finger Knows
- Anime-Planet - Only the Ring Finger Knows
- Minitokyo - Only the Ring Finger Knows Wallpapers and Scans
- WHAT WE KNOW
Only Yesterday
(Omohide Poro Poro)
- Anime Cubed Images: Only Yesterday
- Anime-Planet - Only Yesterday
- Minitokyo - Only Yesterday Wallpapers and Scans
- Nausicaa.Net: Omohide Poro Poro
- Omohide Poro Poro
- THEM Anime Reviews - Only Yesterday
On Your Mark
- Anime Cubed Images: On Your Mark
- Anime-Planet - On Your Mark
- Minitokyo - On Your Mark Wallpapers and Scans
- Nausicaa.Net: On Your Mark
- On Your Mark
Osomatsu
(Osomatsu-kun / Osomatsu-san)
- Ally Rat World - Osomatsu-san
- Anime-Planet - Osomatsu
- Minitokyo - Osomatsu-kun Wallpapers and Scans
- Official Site (Japanese)
- Studio Pierrot - Osomatsu-kun
- The Osomatsu Wiki
Orange
- Anime-Planet - Orange
- Anime-Planet - Orange Mirai
- Longing to Belong
- Minitokyo - Orange Wallpapers and Scans
- Official Anime Site (Japanese)
- Official Site (Japanese)
- Orange (Takano Ichigo) Wiki
- SSE - Orange
Oreimo
(Ore no Imouto ga Konna ni Kawaii Wake ga Nai)
- Anime Cubed Images: Oreimo
- Anime-Planet - Oreimo
- Fall Across the Real Happiness
- Minitokyo - Ore no Imouto ga Konna ni Kawaii Wake ga Nai Wallpapers and Scans
- Official Anime Site (Japanese)
- Official Game Site (Japanese)
- Official Site (Japanese)
- Oreimo Wiki
Otomen
- Anime-Planet - Otomen
- Doki Doki: An Otomen Tribute
- Minitokyo - Otomen Wallpapers and Scans
- Otomen Wiki
- VIZ - Otomen
Ouran High School Host Club
(Ouran Koukou Host Club)
- 1000 Words For Your Smile
- Anime Cubed Images: Ouran High School Host Club
- Anime-Planet - Ouran High School Host Club
- Anime Yume - Ouran High School Host Club
- Apart & Together
- Collected
- Elite: The Ouran Koukou High School Fanlisting
- Equivoque - Hitachiin Kaoru
- FALL IN LOVE
- Foolish Prince
- Funimation - Ouran High School Host Club
- (it's cute!)
- Kind Soul
- Minitokyo - Ouran High School Host Club Wallpapers and Scans
- Official Anime Site (Japanese)
- Official DS Game Site (Japanese)
- Ouran High School Host Club Wiki
- Priceless
- The Nihon Review - Ouran High School Host Club
- theOtaku - Ouran High School Host Club Portal
- Tough Love
- Tricari - Hitachiin Hikaru
- VIZ - Ouran High School Host Club
Outlanders
(Drakuun Ryuuhimehei)
- Anime Cubed Images: Outlanders
- Anime-Planet - Outlanders
- IroIro's Retro Emporium - Outlanders
- Manga Temple: Outlanders
- Minitokyo - Drakuun Wallpapers and Scans
- theOtaku - Outlanders Portal
Outlaw Star
(Seihou Bukyou Outlaw Star)
- Anime Cubed Images: Outlaw Star
- Anime-Planet - Outlaw Star
- Animetric.com - Outlaw Star
- A Simple Shrine to Fred Luo
- Blue Heaven
- Golden Boy
- I Wanna Throw Caution to the Wind!
- Kindred Spirits
- Minitokyo - Outlaw Star Wallpapers and Scans
- Official Site (Japanese)
- Outlaw Star
- Outlaw Star RPG
- OutlawStar the home of Gene Starwind
- Outlaw Star Wiki
- Princess Meg's Top Outlaw Star RPG Page
- RedOutLaw Star (Spanish)
- The Galactic Leyline
- The Nihon Review - Outlaw Star
- theOtaku - Outlaw Star Portal
- The Space Ara