My best friend and me have a friendship like that. It's more like we're brothers in rivalry to be honest.
Sometimes I get on his nerves, sometimes he gets on mine, we compete at everything, we don't really fight a lot anymore these days, but there have been some big conflicts between us at times because we're both stubborn. When it comes down to it though, we make an awesome team in whatever it is we're doing and we'll always have each others' back when the chips are down. Our personalities are like night and day as well Lol
It's probably why we like this manga so much