He's Fushiguro Megumi, not Robin!
At a convention, could you at least make sure who you're talking to before striking up a conversation? It's awkward for the person you mistake, too.
Even if he has a friend who cosplays as Damian, even if that friend went to the bathroom and used him as a coat rack, even if he was forced, and I mean forced, to wear Robin's cape, carry Robin's sword, and stick Robin's mask on his face...
You still can't call him Damian!!
But at this point, there's no use saying any of that.
He's already standing in the desert in the Middle East.
Could you people who pull others into transmigration at least check before you do it? The one cosplaying as Damian is in the bathroom, in the bathroom!
As for what happens next, hehe, I haven't figured it out yet.
Theme: Survive adversity and change yourself