Assflute(ing) is the action of playing an average flute, or one specially designed and shaped for the purpose, with carefully controlled release of air, forced out by the sphincter, causing vibrations which create the sound on their own. However, when an assflute is docked to the anus, the vibrations start at the flute instead of the anus. Due to the difficulty of not only controlling the air flow from your anus, but also playing the flute without being able to see it, Salamander Man, Frank, and Red Dick are the only ones seen fully capable of playing the Assflute, though Salamander Man and Red Dick seem to have mastered it, but only the former is held in high regard by others for his ability to do so.
Filthy Frank himself said, in his video FILTHY FRANK CHIN CHIN SACRIFICE "Let me tell you something, Plastic Pinocchio. Nobody, And I mean nobody plays the assflute better than Salamander Man. He's got some assflute that the world needs to hear, and I'm getting him back.". His Assflute skills even impressed Chin Chin, the dark lord, to the point where he released Salamander despite the fact Filthy Frank not only failed once, but twice to get his own sacrifice for Chin Chin, claiming "I cannot deny the world of true art". He played The Legend of Zelda Main Theme.