A person whom farts into a jar and seals it as a hobby. Jars may vary but pickle jars are typically preferred. Flatulence can also be ranked by level of "Stank".
Person 1: woah dude, why do you have a shelf full of empty jars?
Person 2: Dont worry about it.
Person 1: *internal monologue* "I wonder if he's a Jarfarter"
Person 2: So, you wanna know what's in those jars?
Person 1: No thank you.