It's probably a very important thing to remember as well as who he's guarding.
Her grandson might have magic like her and being closely related to her means that he might be one outlet for the Fey to take advantage of.
All those things considered, Hunter has been given the one job she probably wants to do, but probably can't while keeping the Fey at the party under control. That's a pretty big role to play for Hunter...defending the Queens Grandson in her place and putting his back at risk on the off chance that he might have the same amount of power as the queen that hasn't manifested yet.
Personally, I'm betting that no, he doesn't understand what that means.
And that he's about to get a short, sharp lesson in what she actually means there.
But, as usual, I could very well be wrong...