[@Wick]
Now,
I can post in reply to your post right now, which I already have written
But Wulfric's reply would be terribly condescending. Extremely so, and with perfectly good reason.

Your guards let in a creepy, bad-vibe sort of man straight into a party, who then followed members of the royal family to their chambers, without being challenged, murdered them both, and escaped both the keep- which should be chock-full of guards- and presumably the city without being caught. A murderer literally walked in, murdered whomever he wanted, and ran off without a challenge.

Then your king asked Wulfric, a strange barbaric northern man who's not even been south of the river once until this day, to guard his current heir to his throne. He has no idea if he's looking to take anything valuable and run, or maybe he might rape his new heir the moment he's alone with her. 

I can either post as it is now, or you can go and change it so it's not as... well, awful. This plot twist isn't very well thought-out, and a dozen men with Wulfric could probably take over the entire city with that sort of competence. Medieval times were harsh, and soldiers were more likely to kick someone out on their asses for the smallest things- things much smaller than following the royal family across a throne room, much less into the keep itself, and then into their bedroom.