Stephen Santos was a Werewolf and member of the North American Werewolf Pack until his death. He is the eldest son of Raymond Santos, the nephew of Wally Santos and elder brother of Andrew and Daniel Santos. Stephen followed Malcolm Danvers along with the rest of his family. He was 16 in late 1970 meaning he was born in 1953 or 1954, he'd had his first Change before 1972 and died in 1983 at the age of 29 or 30. He is described at 16 in Savage as a tall teen with long red hair and in Ascension as being more muscular each time the then ten year old Clay saw him.
In the novella Savage he is in attendance at the quarterly Pack meet where Clayton Danvers is introduced to the Pack and becomes an official member. Stephen had yet to undergo his first Change at the age of 16. When Clay was sent down to play with the other Pack children he was bullying Nicholas Sorrentino, upon meeting Clay he shows disdain towards Clay for being bitten, a child Werewolf and in his opinion a mutt. Stephen also calls Gregory Sorrentino a 'retard' and Jeremy Danvers a 'freak' and 'coward'. Clay attacks him in defense of Jeremy and after being separated Stephen claims the attack was unprovoked.
At the Pack meal he again called Gregory Sorrentino a 'retard' and was furious when Clay was invited to eat at the adults table. After lunch he went with Jeremy to be tutored on what to expect for his first Change, a decision he wasn't pleased about.
Stephen appears for the last time in the novella Ascension, a sequel to the previous novella. Having experienced his first Changes at this point he was one of the participants in a deer hunt and waited impatiently for his turn to eat. When Clay went to go find his own meal to hunt Stephen followed him and attempted to take it from him. Malcolm later invited him to spend time at Stonehaven to torment Jeremy. He attended the last Pack meeting Dominic Sorrentino held as Alpha before he suffered a stroke in 1982, he was annoyed with Clay's actions scaring away mutts as it meant they now had to go find them themselves and even then the mutts would often run away.
He voted for Malcolm as Alpha at Dominic's wake and continued to support him. Six months later in April of 1983 Malcolm had him shoot Nicholas Sorrentino with his rifle as part of a failed plot to isolate and kill Jeremy. Clay knew it was him as he was the only one who knew how to shoot and his boots had Stonehaven's mud on them.
He later returned to Stonehaven as part of another plot to kill Jeremy Danvers, he expressed the belief he could take Jeremy with one arm behind his back as well as his displeasure at Malcolm's insistence that Clay be left alive, suggesting they 'accidentally' kill Clay. He was stopped from attacking Jeremy by Clay who fought him and told him he was killing him because eventually it would come to this again and Stephen himself wouldn't have shown mercy, he broke Stephen's arm and then his neck.
- The Santos family are mentioned to live in Pennsylvania.
- Stephen was raised as a follower of Malcolm Danvers by his father and uncle and is shown to parrot their opinions and beliefs as fact without ever doubting them or forming an opinion for himself. He continued this behavior with his own brothers, encouraging and rewarding Daniel when he joined in with Stephen's attempts to bully and insult Clay.
- He is known to have sought out mutts to fight after Clay made his reputation, before this he had to be careful when travelling as a mutt who had settled into a city would attack him if he came across them.
- He had friends, presumably humans, who were hunters and owned a rifle that he knew how to use. Generally Werewolves view using weapons as a weakness although he may have only used it for hunting outside of shooting Nicholas Sorrentino under Malcolm's orders.
- He is shown to be jealous of Malcolm's fondness of Clayton Danvers, mentioning that he and his brothers are the ones who follow him and yet Clay is the one to get his special attention.