The main character told the tiger guy in the first chapter that they're brothers so that he wouldn't get killed, but they're not actually brothers. So it's not incest. The tiger guy just thinks that they are because he is naive, and the main character is pretending so ofc he'll call the guy hyung(but also guys can call their older friends hyung, they don't have to be brothers. It just means they're close)

Is this incest or just a confusingly translated hyung