I wonder if he wants to scope out WHO his sister is talking to often, enough to dress up and possibly meet, from the game.
he obvs cares about her in his own way and she acted suspicious af so he's resorting to this. gonna be WILD if Sprinkle Flower invs Ajin to bocochat and hes like HUH when a guy speaks and her brother hears a guy on the other side also ((I kinda hope this happens HAHA))