Like I said, you don't have to explain! It's TOTALLY fine, and like you said it adds another layer of complexity for their relationship, which is great! They can and should still be flirty silly friends together. He feels pretty protective towards her, after all, and really does cherish her for the perfect little cinnamon roll she is, so if and when she gets her poor heart broken, you know he'll be there to bash heads. And if and when she wants to make with the smoochies, he's down for that too XD