<human>: Can you provide a brief rundown of the text in within 3 sentences?

So we have known this guy most of our lives, i'll call him M. Him and my brother (same age) met at school and us and our familes have become pretty close. Whenever he comes over usually I hang out with them too because i'm a lot like them. He always comes over for my brother and never really talks to me apart from when he is at my house. 

So just recently, when we all hung out (me, M, my brother, and some other of our friends) M put his arm around me casually when we were all sitting on the couch. Obviously I didn't think it was meant as anything, and he did it off and on the whole time he was there and started rubbing my arm too. Another time he came I invited my friend over too and she and my mom saw him doing it. 

The next time he came we were sitting on the couch again and we all were under a big blanket and he started rubbing his hand up and down my thigh under the blanket. Again I still thought he was just doing it for no reason or he didn't think it was me or something. 

Whenever we talk he never acts like he is interested in me or anything and he barely even talks to me period. Everyone keeps telling me he likes me but I don't think he does. I don't know if I want to ask him because it would be embarassing. What should I do?
<bot>: My brother and I's lifelong friend put his arm around me multiple times and rubbed his hand up and down my thigh under a blanket, but I think he was just doing it by accident.