I wonder who Al's "natural enemy" is. My first thought would be Subaru but obviously he's trapped. So maybe Petra since she has the "ghost Subaru" but does Al know that. Or maybe Roswaal just because he's so powerful. Not sure.

Also very curious to find out the proper relationship between Al and Emilia, he doesn't want to hurt her and he's not enjoying being confronted by her here either.

And was that Roy releasing someone's name and/or memories? I wonder who, main guess would be Rem, Julius or Joshua. More likely one Rem or Julius for it to have impacted Emilia a decent bit. And then what did Roy mean at the end with the thanks for the treat, who did he eat?