Remus couldn't help but think that more than him, she was the one more likely to make a false move. But he made no comments about it as he nodded instead to her and called out, "Of course. I completely understand." In his mind, he was chanting, Protegoprotegoprotego... in case he needed a quick shielding spell.
With his suitcase, he stepped back, giving her space and giving him space should he need to retaliate. It was obvious on Remus' stance that he was still on his guard -- but if your cheek swelled twice its normal size and your fingers wanted their fingernails back, then it was no wonder you'd be on edge.