User blog comment:Miskos3/Fairy Tail Chapter 368: The Third Seal, Review/@comment-3424593-20140124123855/@comment-7418318-20140124132653

I agree. Cana was never one to verbally hold back, so she's the perfect person to provoke Elfman without it seeming out of place.

But at the same time she's smart enough and knows Elfman long enough to figure out that something's wrong. Lucy might be smart enough to pull something similar off, but she doesn't know Elfman well enough to notice and her mind's probably occupied with Natsu's and Erza's capture.

I wonder if Cana only noticed something was wrong due to Elfman's reactions to her nagging, or if she intentionally nagged him to confirm some odd feeling she already had.