| SethセトO | |
| Aliases | Seto |
| Birthday | 7 January |
| Hair | Ahoge, Black, Multicolored, Short, Spiky Bangs, White |
| Eyes | Grey |
| Body | Kid, Pale, Short (obsolete), Slim |
| Clothes | Jacket, Scarf, Trousers |
| Personality | Honest, Opposite Gender Voiced, Shy |
| Visual novels | Makes an appearance - UNDER NIGHT IN-BIRTH |
| Voiced by | Aimi |
| SethセトO | |
| Aliases | Seto |
| Measurements | Height: 169cm, Weight: 49kg |
| Birthday | 7 January |
| Hair | Ahoge, Black, Multicolored, Short, Spiky Bangs, White |
| Eyes | Grey, Slit Pupils |
| Body | Pale, Slim, Teen |
| Clothes | Belt, Tailcoat, Torn Clothing, Trousers, Turtleneck Shirt |
| Items | Dual-Wield Weapon, Knife, Named Weapon |
| Personality | Blunt, Distrustful, Loner, Reserved, Secretive, Serious, Stoic, Taciturn |
| Role | Superhuman |
| Engages in | Fighting |
| Visual novels | Side character - UNDER NIGHT IN-BIRTH |
| Voiced by | Kaji Yuuki |