- obake no holly (1)
- obakeidoro (1)
- obey me one master to rule them all (1)
- obi wo gyuttone (4)
- oboro muramasa (43)
- occult academy (81)
- occultic nine (63)
- ocha nigosu. (1)
- ochame na futago (5)
- ochamegami monogatari korokoro pollon (5)
- ochikobore fruit tart (20)
- octopath traveler (23)
- oda nobuna no yabou (97)
- odd taxi (22)
- odin crown (2)
- odin sphere (66)
- odoru daisousasen (9)
- off (1)
- oh edo rocket (2)
- ohayou spank (1)
- ohsama sentai king-ohger (1)
- oide yo mizuryuu kei land (125)
- oira uchuu no tankoufu (2)
- ojama yurei-kun (2)
- ojamajo doremi (1063)
- ojisan to marshmallow (4)
- ojousama express (1)
- ok k.o. lets be heroes (3)
- okami (15)
- okhotsk ni kiyu hokkaido rensa satsujin jiken (1)
- oku-sama wa joshi kousei (11)
- okujou no yurirei-san (9)
- okusama ga seito kaichou (7)
- okusama wa mahou shoujo (8)
- okusan (71)
- ole tower (6)
- omae umasou da na (7)
- omae wo otaku ni shiteyaru kara ore wo riaju ni shite kure (2)
- omaera zenin mendokusai (2)
- omakase peace denkiten (3)
- omamori himari (9)
- omegane teacher (1)
- omishi magical theater risky safety (8)
- omoide no marnie (1)
- omoikkiri kagaku adventure sou nanda (33)
- omori (5)
- one kagayaku kisetsu e (39)
- one off (2)
- one outs (2)
- one piece (3714)
- one punch man (757)
- one room (1)
- one week friends (33)
- onechambara bikini samurai squad (1)
- onegai anna sensei (2)
- onegai asakura-san (1)
- onegai my melody (187)
- onegai ranking (4)
- onegai teacher (455)
- onegai twins (150)
- oneshot (11)
- ongeki (8)
- oni chichi (19)
- onidere (10)
- onigokko (5)
- onihime vs (18)
- onii-chan asa made zutto gyutte shite yoru made motto ecchi shite (4)
- onii-chan dakedo ai sae areba kankeinai yo ne (38)
- onii-chan wa oshimai (145)
- oniichan no koto nanka zenzen suki janain dakara ne (9)
- oniisama e... (1)
- oniku daisuki zeushi-kun (1)
- onimusha (24)
- only yesterday (1)
- only you (4)
- onmyoji (76)
- onmyou taisenki (136)
- onward (1)
- ookami kodomo no ame to yuki (20)
- ookami-san to shichinin no nakama-tachi (79)
- ookii onnanoko wa suki desu ka (12)
- ookiku furikabutte (321)
- ookumo-chan flashback (1)
- ooyasan wa shishunki (19)
- operation darkness (1)
- ore ga suki nano wa imouto dakedo imouto ja nai (4)
- ore monogatari (6)
- ore no imouto ga konna ni kawaii wake ga nai (1890)
- ore no kanojo to osananajimi ga shuraba sugiru (24)
- ore no natsuyasumi (7)
- ore no nounai sentakushi ga gakuen love comedy wo zenryoku de jama shiteiru (16)
- ore no shikabane wo koeteyuke (10)
- ore o suki nano wa omae dake kayo (6)
- ore twintail ni narimasu. (120)
- ore yuuko (2)
- oretachi ni tsubasa wa nai (5)
- orfina (2)
- ori and the blind forest (3)
- ori no naka no soloist (1)
- orichalcum reycal (1)
- original (148427)
- orion heart (3)
- os-tan (130)
- osana najimi wa bed yakuza (21)
- osananajimi ga zettai ni makenai love comedy (6)
- osawari island (11)
- oshi ga budoukan ittekuretara shinu (3)
- oshi no ko (112)
- oshiete galko-chan (273)
- oshioki sweetie (32)
- oshiro project (65)
- osomatsu-san (494)
- otaku no musume-san (2)
- otaku no video (17)
- otenki studio (1)
- otocadoll (1)
- otogi matsuri (1)
- otogi-jushi akazukin (83)
- otokonoko wa maid fuku ga osuki (20)
- otome crisis (1)
- otome game no hametsu flag shika nai akuyaku reijou ni tensei shiteshimatta... (62)
- otome game sekai wa mob ni kibishii sekai desu (9)
- otome renshin prister (3)
- otome wa boku ni koishiteru (56)
- otome youkai zakuro (8)
- otomedius (8)
- otometeki koi kakumei love revo (1)
- otonari no tenshi-sama ni itsunomanika dame ningen ni sareteita ken (10)
- otoyomegatari (30)
- ouchi ni kaeru made ga mashimaro desu (4)
- ouendan (6)
- ougon senshi gold lightan (1)
- ougon yuusha goldran (3)
- oumagadoki zoo (7)
- ouran high school host club (73)
- ousama game (2)
- ousama ranking (9)
- outbreak company (69)
- outer zone (25)
- outlanders (31)
- outlast (4)
- outlaw star (67)
- overlord (356)
- overlord bob (2)
- overman king gainer (62)
- overwatch (411)
- owari no chronicle (1)
- owari no seraph (96)
- oyakodon oppai tokumori bonyuu tsuyudaku de (3)
- oyoneko buunyan (1)
- oz (1)
- ozanari dungeon (2)