| Oops, a Cannibal Got Your Nose! | r113897 | 2026-05-13 |
| Oose no Mama ni ★ Goshujin-sama! - Download Edition | r20387 | 2026-05-15 |
| Oozora o Mau Chou no You ni | r118909 | 2026-05-19 |
| Open DayS | r2670 | 2026-05-16 |
| Open Heart: Book 1 | r66537 | 2026-05-19 |
| Open Heart: Second Year | r66538 | 2026-04-21 |
| Open Heart: Third Year | r76823 | 2026-04-21 |
| Open Hearts on Fire | r136391 | 2026-05-16 |
| Open Love Surgery | r126574 | 2026-04-21 |
| Open Spaces - Ludum Dare 42 Version | r58631 | 2026-05-12 |
| Open Spaces - Beta Edition | r93033 | 2026-04-21 |
| Open Spaces SE (Standard Edition) | r93031 | 2026-05-14 |
| Open Spaces SE Demo | r93032 | 2026-04-21 |
| Open UP | r139377 | 2026-04-21 |
| Open the Door | r142303 | 2026-05-16 |
| OpenFlower | r109665 | 2026-04-21 |
| Opened Eyes v0.4 | r112516 | 2026-04-21 |
| Opening Up: Hazel's Story - Demo | r107822 | 2026-05-15 |
| Opening Up: Hazel's Story v0.1 | r107823 | 2026-05-19 |
| Operacija «Spadok konstruktora» | r125984 | 2026-05-19 |
| Operation Eventide - Censored Edition | r146764 | 2026-04-21 |
| Operation Eventide - Definitive Edition | r149179 | 2026-05-10 |
| Operation Eventide - Demo | r147021 | 2026-05-11 |
| Operation Eventide 2.0 | r133436 | 2026-04-21 |
| Operation Eventide: DOLOROSA | r141330 | 2026-05-06 |
| Operation NOVEL: Season 1 | r78936 | 2026-04-21 |
| Operation: Future Domination - Demo | r52407 | 2026-04-21 |
| Operation: Matchmaker | r101770 | 2026-04-21 |
| Operation: Val-O-Gram | r78264 | 2026-04-21 |
| Operation‡Nova | r95956 | 2026-05-16 |
| Operation‡Nova | r109326 | 2026-04-21 |
| Opia | r119374 | 2026-04-21 |
| Opia - ver. 1.1 | r124582 | 2026-04-21 |
| Opium Eater | r34642 | 2026-05-20 |
| Opjat' Odin v1.26.02 | r92669 | 2026-05-12 |
| Opona - Demo | r71681 | 2026-05-19 |
| Oppai Baka -Oppai Igai wa Mitomenai!!- | r3513 | 2026-05-11 |
| Oppai Baka ~An Idiot for TITS, In a World Full of TITS!!~ | r133880 | 2026-04-21 |
| Oppai Cafe. La mère, la fille et leur poitrines fourbes | r54317 | 2026-04-21 |
| Oppai Cafe. My mother, my sister and Me | r119124 | 2026-05-19 |
| Oppai Cafe. My mother, my sister and Me | r62586 | 2026-05-15 |
| Oppai Cafe. My mother, my sister and Me | r63134 | 2026-04-21 |
| Oppai Café ~Oyako de Cos Chichi~ | r77286 | 2026-05-19 |
| Oppai Café ~Oyako de Cos Chichi~ Package Edition | r50349 | 2026-05-16 |
| Oppai Chiisakute Nani ga Warui no sa! - Download Edition | r11763 | 2026-05-18 |
| Oppai Dekai!! Nurse to Ichakora Ero×2 Nyuuin Seikatsu!? | r146820 | 2026-04-21 |
| Oppai Dekai!! Nurse to Ichakora Ero×2 Nyuuin Seikatsu!? [AI +Edited TL] | r148437 | 2026-04-21 |
| Oppai Gakuen Marching Band Bu! ~Hatsujou Hamedori Katsudou Nisshi~ | r15789 | 2026-05-19 |
| Oppai Gakuen Marching Band Bu! ~Hatsujou Hamedori Katsudou Nisshi~ | r116231 | 2026-04-21 |
| Oppai Gakuen Marching Band Bu! ~Hatsujou Hamedori Katsudou Nisshi~ Low Price Edition | r36287 | 2026-05-20 |