Cooper's a little jumpy thanks to Abigail's warning about the house possibly being more than just a normal manor. Combine this with the creepy portraits and he's quite on edge. He whirls around when he hears Aradia's voice. He didn't hear or smell her coming up, which in and of itself is unusual. What a way to make an entrance.

His heart pounds in his chest, but his voice is steady as he answers. "It's certainly strange. Wonder if it has to do with the family curse."