It looks to me that Adora fell out of the amulet and bumped into Ace as she did, rather than was immediately trying to succubus on him.
It also looks like Nina is the downfall of Chloe, as it probably should be. Now they've got someone on board who has explicit, intimate knowledge of the Doompanties and their effects, and presumably how to counteract them. Of course, I doubt it's going to be so straight forward as that and will probably involve an Elaborate Caper by her, Are, Nina, and Brooke. Presumably Layla will be mixed in there as well when she turns up. If 80s films have taught us nothing, Queen Bees who hold dances at school and have wronged an ensemble cast can only be given public comeuppance by way of Caper.