Four Knights of the Apocalypse: spoilers:end of spoilers
Oh King and Diane. You really could've handled this Mertyl-situation better. By which I mean talking to him about his place in the family and clarifying that you truly love him as your son. Really should've made that clearer.
But you seem to have the intruder bit well in hand. Kick their asses!
Blue Exorcist: spoilers:end of spoilers
Some cool action scenes against Amon and Asmodeus (they are totally jumping back up at some point, no way are they dead). And a really sad goodbye to Osceola. For a character that I honestly always thought was just kinda there (though he did have some nice scenes here and there), I think that this was a well done death.
Hits all the right notes, gives more insight into both Osceola and Lewin, and gives a good taste of what's to come for the rest of this raid. And he went out like a badass. Good stuff.
Now it's dungeon crawling time.