Little is known about the character himself as he never speaks, however certain aspects of him can be attained through observations in his apartment, such as the possibility that he plays video games, noted by his games console in his bedroom.
It is heavily implied over the course of his one-man-war on the Russian mob that he may at least be mentally unstable, as he will begin to hallucinate talking corpses as the story progresses. Despite this, he is a merciless psychopath who soon learns to kill without hesitation; his first day of massacring forces him to throw up, however every excursion after that he swiftly proceeds to kill whoever he is told seemingly without reservation.
He does, however, show mercy towards an abused hooker, whom he saves and then begins a romantic relationship with, as shown via their beds moving closer in the apartment between missions. The hooker is killed by Russian operatives seeking revenge towards the end of the game, and Jacket's reaction is unstated.
Jacket makes sporadic appearances in Hotline Miami 2, characterized as a sort of malicious echo of his past actions that follows and taunts the many protagonists of the game.
- It is rumored that his first name may be Richard, as it's the very first mask he acquires in the game and every mask is named after their owner. Furthermore, in Hotline Miami 2 Jacket is shown to be wearing the Richard mask also.