A "Friendship symbol"

Prompt - "Person A excitedly telling person B that they made a bunch of new friends and says "they even showed me this cool symbol" and person B says "THAT'S A GANG SYMBOL, YOU ACCIDENTALLY JOINED A GANG!"

This just screamed Simon from Shadowhunter's to me. :)
This uses Shadowhunter's characters (not mine, all credit to original author) but in an alternate universe I made.
This is a prompt I saw on Pinterest.