Oomuro-ke: Dear Friends
Osomatsu-san: Tamashii no Takoyaki Party to Densetsu no Otomarikai
Osomatsu-san: Ouma de Kobanashi
Ore no Imouto ga Konnani Kawaii Wake ga Nai.: Ore no Imouto ga Konnani Eroge na Wake Nai
Outbreak Company
Onimai: I'm Now Your Sister!
Onipan!
ORESUKI Are you the only one who loves me? - I Politely Move Things Forward
Oomuro-ke: Dear Sisters
Ozmafia!!
Otoboku: Maidens are Falling for Me! Special
Overlord: Ple Ple Pleiades 2