Hostile shooters should avoid shooting right next to the demon. Kind of unfair if you can’t shoot back.
After killing their first target, it appears they target the player that dealt the most damage to them. It could be changed that the demon becomes more like the other bosses after killing his first target, but still leaves if a second player dies.
Right now, if you know your team is bad, best thing to do is to run away and hope someone else is targeted second. I’m sick of getting punished because someone else made a mistake and I’m the only one trying to help.