We're in middle school. Ok, so me and my crush are really close friends and also good friends. Anyways I had gave him some advice about his girl bestfriend (and also my friend) and then he said thankyou afterwards and I said "aye that's what friends are for". A little later after I said that he had tapped me and he was smiling and he had put his hand over his heart and said "Aye I got your back". And I just smiled. So, what does it mean when a guy says "I got your back"? Please, no negative comments.