When you make a status about your best friend (just that one best mother fucking friend to the end and beyond that) on FB and tag them and they do the same for you. Usually comes after you and said bro have a deep conversation about how good bros you are.
(insert name) Best Friend since kindergarten, through Wolftrap, through Kilmer when we both went to different schools, and now. Next year is going to be sick. Cant wait for your ass at Marshall