- (Film) Geckos-There isn't much known about the Gecko Family in the films, other than Seth and Richie have been criminals for some time.
- (TV) Geckos-The family is full of criminals. When they were younger, Richie had set their house on fire and killed his and Seth's father. Afterwards, they are taken in by Eddie and he trains them in everything he knows about the criminal world. Seth and Richie have done 35 jobs before Seth's incarceration and Richie later broke him out.
- Seth Gecko (Film)-The older brother of Richie and one of two survivors of the Titty Twister.
- Richard Gecko (Film)-The younger brother of Seth and was turned into a vampire by Santánico Pandemonium. He is later killed by Seth.
- Seth Gecko (TV) (1980s-)-The older brother of Richie and the son of an unnamed woman and Ray Gecko. He is a criminal like his father, younger brother and adopted uncle.
- Richie Gecko (TV) (1980s-)-The younger brother of Seth and the son of an unnamed woman and Ray Gecko. He is a criminal like his brother and has recently become a culebra.
- Ray Gecko (?-?)-The father of Richie and Seth. He was killed in a house fire set by Richie.
- Unnamed Woman (?-)-The mother of Seth and Richie, and the former wife of Ray.
- Eddie Cruickshank (?-2014)-He is considered the uncle of Seth and Richie, as Seth states he's like family and he had taken them in when Seth and Richie's father died. He is killed by The Regulator after he tries to help the brothers and Santánico.
- Vanessa Styles-Seth's ex wife who is currently doing time in a women's prison.