A person that is a "friend" but is treated very poorly, and is only used as a second option incase their #1 friend isnt around.

back-up friends may be ignored, and not invited to things.
a back-up person are in a trio relationship of any kind

they may be that friend that walks behind the group when they are talking about something they didnt go to, and the friend that gets left on read in the groupchat and gets called annoying.
"I feel like a back-up friend when im around her." -1
"im sorry for you" -2
by Da.weirdo July 5, 2022
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This word orginated from fuck boy" and has been expanded upon. Where a friend has the same intention as a "fuck boy" but only as a friend. Where you ask said friend "hey Tim would you like to go fishing and his response is Ya sure then blows you off later and then gives you a lame excuse that he has to help his dad do his taxes. Like come on a retarded kid doing taxes for a very intelligent man. Here are signs that your friend is a "fucked up friend boy". He makes plans, you show up and follow through then he blows you off. Then Timmay plays it as "o" well I meant to come but this girl texted me and I had to drive like 120 miles in my new car and still did not get laid even after sleeping in the same bed and proceeds to say we should hang out this next weekend. Just enough conversation and interaction to lead you on that your still friends.
Hey Jimmay you want to hang out such but I won't show up like the last time oh OK cool. Fucked up friend boy
by hue jasol March 14, 2018
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