Although I am an adult i recently found a pair of my dirty underwear underneath the bed of my brother. I am veeeeery grossed out by this and I don't know what to do. Why on earth would a man steal any woman's under wear. I did some research on this and it said that mostly younger boys do this,but my bro. is 31!!!!!! What is going on here and is that normal?

I am just sick to my stomach right now.

btw i am 21. i have not mentioned to him that i find some of my undies in his room bc i know it'd be embarassing but @ the same time what kind of behavior is this???!