Otherworldly Munchkin: Let's Speedrun the Dungeon with Only 1 HP!
Overlord IV
Onihei
Overlord: Ple Ple Pleiades - Nazarick Saidai no Kiki
Oretachi ni Tsubasa wa Nai: Hadairo Ritsu Kyuuwari Zou!?
Orphen 2: Revenge
Overlord: The Dark Hero
Orphen
Ozma
Orient
Overlord II
Orient: Awajishima Gekitou-hen