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| Onii-chan Teacher ~Himitsu no Jugyou o Kibou Shimasu!~ | 2015-12-25 | 6.80 (81) |
| Onii-chan Yamete | 2002-04-26 | - (1) |
| Onii-chan Yamete 2 | 2003-09-19 | - (2) |
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| Onii-chan no Ofuro Soudanshitsu | 2014-04-29 | 6.10 (20) |
| Onii-chan no Otoshikata ~Futago no Shimai Hen~ | 2012-01-07 | - |
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| Onii-chan to Boku Extra Edition!! ~Subaru vs Kaoru Isshuukan Gentei Minato Soudatsu Sen~ | 2016-02-05 | - |
| Onii-chan to Issho | 1999-04-23 | - (3) |
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| Onii-chan to Watashi | 2026-03-06 | - |
| Onii-chan to, Futago to, Imouto to. | 2005-04-18 | - (1) |
| Onii-chan wa Chuunibyou | 2014-08-17 | - (1) |
| Onii-chan wa Shokushu | 2004-04 | - |
| Onii-chan ♥ I Think I Wanna Have Your Baby! | - | - |
| Onii-chan!! Shasei no Kanri wa Imouto ni Makasete!! | 2015-12-18 | 7.10 (58) |
| Onii-chan, Asa made Zutto Gyutte Shite! | 2018-05-25 | 7.40 (511) |
| Onii-chan, Asa made Zutto Gyutte Shite! Yoru Made Motto Ecchi Shite! | 2019-06-28 | 7.60 (188) |
| Onii-chan, Date Desu! 2 | 2019-06-29 | - |
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| Onii-chan, Migite no Shiyou o Kinshi Shimasu! | 2014-09-26 | 7.10 (155) |
| Onii-chan, Migite no Shiyou o Kinshi Shimasu! 2 | 2017-09-29 | 5.80 (42) |
| Onii-chan, Oshiete... ~Gimai to Himitsu no Hoken Jisshuu~ | 2015-12-25 | 5.70 (28) |
| Onii-chan, Tetsudatte! ~Yoru no Hanayome Shuugyou o Tanomarete...~ | 2022-04-28 | 5.90 (26) |
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| Onii-san to Issho - Chokotto+ | 2011-02-25 | - |
| Onii-tan to Pishuton Gokko! | 2012-10-22 | 6.50 (22) |
| Oniichan Continue! | 2025-08-17 | 6.80 (62) |
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| Oniichan to Issho! Happy Birthday!! | 2003 | - |
| Onikakushida yo! Dokuro-chan | 2005 | - (4) |
| Onikiri-den | 2000-01-21 | - |
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| Oningyou Yamaa Yumashou Kudanzaka Kaiki Sousho 2 | 2024-05-06 | - (1) |
| Oningyou de Asobou | - | - |
| Onirio | - | - |
| Onitori+ | 2008-08-16 | - (1) |
| Onitsubaki 2 ~the end of the love~ | 2005-08-14 | - |
| Oniyadori | 2020-12-07 | - |
| Oniyarai Mura | 2007-08-17 | - |
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| Onizukin | 2011-04-27 | - |
| Online @ The Perfect Time | - | - |