Characters
- ouka shiunji 2
- ouka tenjouin 1
- oumi 4
- oumiya emma 1
- ouran nakagawa 1
- ouro kronii 498
- ouroboros 7
- outis 16
- outrun 1
- outworld destroyer 1
- ouya ootani 7
- ouzou furuya 12
- ovelia atkascha 18
- owain 6
- owari 52
- owen 5
- ox-king 15
- oyashio 50
- oyuki 54
- oz 1
- ozai 3
- ozen 56
- ozma lee 3
- ozorotter 1
- ozu 1
- ozymandias 56