I'm a skin-picker. I go through random periods where I pick the skin on my toes until they bleed, or the skin on my thumbs. I also endlessly chew the inside of my mouth. I cannot stop. I have been doing that for over 25 years. I also pick scabs, pimples, scars, anything that is not smooth on my skin. I saw on YouTube there were some videos by a certain doctor that depicted the squeezing of cysts while calming music was playing - LOL! It is supposed to help us skin-pickers to suppress our innate desire to do damage to our skin. I wish I could recall the name of the user who posted the videos.

HTH.