So I have a friend group of about nine people, and one of them keeps taking random things from my house. They are all small useless things (pens, dice, lighters) and very cheap and inexpensive. At first I just thought I was losing things, but I keep seeing him acting weird in my house, in rooms seemingly doing nothing or staring at the mantle piece. But I know he is stealing things, as I saw one of my matchbox cars on his desk, along with a few other things that had gone missing. Anyway, I told my other friends about my suspicions, and one confronted him about it, to which he just smirked and changed the topic. But recently he has been getting much more defensive when anyone mentions this. (I presume I'm not the only one he does this to.) My main concern is why he is doing this. And of course there is a possibility that I'm just losing things aswell, which keeps bugging me. So, AITAH?