That sounds reasonable. I was thinking something like that, and since Rodrick is one of the most cautious people alive, he won't be making any bad decisions. Mutual respect would be the best word for it, I agree.
Well, the first thing we should do is take a look at how our characters are connected:
Your character is Erika's personal body guard.
My character is related to Erika.
Your character is the Captain of the Guardians(which sounds like a cheesy 90's cartoon)
My character is a Guardian.
So it goes without saying that your character would be the one giving orders to mine. But I think as far as personal relations go, I feel like it would be somewhat of mutual respect for one another. My character would respect yours as a leader and follow direction, and your's would respect mine as an exceptional subordinate and not be a dick to him.
I'm making my character out to be a warrior/scout with skewed ideals, but he's still a respectable military man and not the scheming type. So you won't see my character butting heads with yours unless you plan of making very rash calls