Guy friend grabbed my boob?

I have a male friend, we've been friends for about 7 years now. We met because I was dating one of his friends and shortly after we broke up he approached me for a friends with benefits type scenario. I declined and we became good friends. He's never mentioned anything like that since, but recently he has grabbed my boob on two different occasions. Do guys do this to their female friends?
Guy friend grabbed my boob?
Post Opinion