Jason's background
Rockstar says Jason grew up around grifters and crooks. After a troubled adolescence, he joined the Army and later ended up in the Keys working for local drug runners.
His official profile frames him as someone who wants an easier life but keeps being pulled into risk. Meeting Lucia may become either the best or worst event of his life.
Jason and Lucia
The pair sit at the center of GTA VI's story. An easy score goes wrong, drawing them into a criminal conspiracy across Leonida and forcing them to depend on each other.
What is still unknown
Rockstar has not published Jason's full ability set, progression path or exact character-switching rules. Those details remain open until an official explanation or hands-on verification is available.