This brings back a memory... this is like 20 years ago and our early 20's, we had one friend who went through a weird phase of self harm, but only around people and it got worse the drunker we got through the night. We all had no idea why, and we all got weirded out by it. Anyway, this reminded me of the time he carried around a glass jar with barbed wire inside and other things to cut you with $5 at the bottom. I believe he copied a scene in family guy. He kept asking people to try, and of course nobody would, so he would then say look its not hard and jam his hand inside. It was super creepy, and we think he enjoyed seeing us squirm and squint our eyes. During this same phase one night he carried around a kitchen knife, and he actually ended up stabbing our friend in the leg as he looked at us in horror and us back at him the same. Let's just say he isn't really friends with most of us anymore and also moved thousands of miles away.