originates from the word "winrawr" one who wins, or to win.
Friendrawr is the mutual win of two friends. They both win because they are two awesome people that have each other for an awesome friend.
Lexi: I love eggdrop soup.
Zane: Really? me too! no one else i know likes it.
Lexi: Sweet! We are friendrawr!
Cheyanne: Lexi and Zane have so much in common.
Sam: Yeah, they're definitely friendrawr.