Good Brother

A Good Brother is a friend, usually male, who will go out of his way for other male friends to make sure they are okay and got what they need—usually, the first one to step next to you during a fight.

Popularized by the pro wrestling tag team "The Good Brothers." Who often stick near their close friend AJ Styles.

Jim, " Man I can't believe you helped with the bar tab and helped me scare off those biker dudes."
Jack, "It's okay man, just being a Good Brother."