The Prison Counselor is a worker at the Gravity Falls Maximum Security Prison.
In "Weirdmageddon Part 1," he tells several prisoners that their finger paintings are good before coming to Gideon's and gasping. The counselor tells Gideon that his painting does not make him look like he is ready to re-enter society. Shortly after, the counselor is crushed by rubble when the building is knocked over by a gargantuan Gompers, likely killing him as well.
The counselor is a heavyset man with a small, dark brown mustache. He is mostly bald, only having hair on the back and sides of his head. He wears square glasses, a light blue dress shirt and a brown apron.