I feel like Francel is going to become our enemy. His anger at us is understandable; we took his best friend and protector from him. He likely resents us for the ease we won him over, and the (potential) relationship we had with him.
What I found odd is that the story suggested that the relationship between Haurchefant and Francel was just between a knight and his lord; there was a distinct lack of romantic undertones (as is suggested by the early MSQ). But I get the feeling Francel wanted more, and is jealous the WoL (potentially) got that.