| Name | Total | ... |
|---|---|---|
| Ooi | 17 | GO |
| Oolong | 2 | GO |
| Ooshio | 1 | GO |
| Ooyodo | 16 | GO |
| Oozora Subaru | 0 | GO |
| Operator 21O | 2 | GO |
| Operator 6O | 1 | GO |
| Ophelia Phamrsolone | 1 | GO |
| Ophiuchus Shaina | 2 | GO |
| Orange Pekoe | 14 | GO |
| Orba | 1 | GO |
| Orchid / Orchis | 2 | GO |
| Orga Itsuka | 2 | GO |
| Oriana Thomson | 9 | GO |
| Origami Tobiichi | 2 | GO |
| Original | 1 | GO |
| Orihime Inoue | 46 | GO |
| Orion/Artemis | 2 | GO |
| Orochi | 5 | GO |
| Orochimaru | 1 | GO |
| Orsola Aquinas | 7 | GO |
| Ortlinde NBLG Valkyria | 1 | GO |
| Osakabehime | 11 | GO |
| Osama bin Laden | 1 | GO |
| Oshawott | 1 | GO |
| Oshino Meme | 4 | GO |
| Oshino Shinobu | 54 | GO |
| Osomatsu Matsuno | 2 | GO |
| Oswald | 1 | GO |
| Otako | 6 | GO |
| Otao | 2 | GO |
| Otoha Sakurano | 1 | GO |
| Otohime Ryuuguu | 1 | GO |
| Otome Arisugawa | 1 | GO |
| Otome Asakura | 3 | GO |
| Otonoshin Koito | 2 | GO |