Coming from a poverty-stricken Edonian family, Jake became a mercenary early on in order to afford medical treatment for his chronically ill mother, who died shortly thereafter. Left alone in the world, he turned his only concern into monetary gains. His life comes to a turning point when he meets Sherry Birkin, who claims he's the world's best hope of salvation — and learns his father, who left his pregnant mother, was none other than Albert Wesker. It is then revealed that Jake has inherited many of Alber Wesker's abilities from Umbrella's Wesker Eugenics Program, mainly Wesker's physical prowess and augmented immune system.
Personality and Traits
All right, first thing's first. Two hundred thousand up front, another two hundred when this is over. And the B.O.W.s? Those are extra.
~ Jake to Sherry on getting paid higher.
In the first glance, he's much more concerned about how much money he could earn with his blood rather than saving the world. It seems that Jake's jokes, taunts, and boasting might just be bravado on his part. But it eventually becomes clear that he means what he says, and he really is having fun fighting zombie hordes. He refers to the Ustanak as his personal punching bag without irony, after about the fourth time that it came within a hairs-breath of killing him and Sherry. When they team up with Leon and Helena to battle the Ustanak in Lanshiang, Jake freely admits that he lives for stuff like this, causing Helena to question his sanity.
However, by the end of the game, he graduates to a much more heroic and self-sacrificing character. It is shown when he slowly starts to care, until he's genuinely trying to help Sherry save the world instead of just doing it for the money. Jake becomes more protective, shoving Leon when he attempts to get close to Sherry when in China. After the events in China, he lowered his price, and decided to change his life, shown when protecting a child from Napads.