RPF (Resting Prison Face)

Resting Prison Face is the phenomena of someone making a particularly menacing or unapproachable face when outside, at all times. Also see resting bitch face for a similar effect.

Friend: "What's with your face bro are you angry or something"

Friend 2: "that's just my RPF (resting prison face)"

Friend: "oh, RPF bro, I get it