Usually, whether she was aware of it or not, there used to be a dominant and a submissive part in relationships. Despite these words' different nuances, they weren't really a good thing or a bad thing; it was just the way things were. To begin with, these roles could vary greatly and completely change in a healthy relationship depending on the setting.
The average person was always more inclined towards one of these two roles. In Fei Long's case, she used to be the dominant part of their relationship, and Xiauyue was the submissive part. It wasn't a matter of respect or love; it was just the mechanics of their relationship. However, on infrequent occasions, Xiauyue could be pretty domineering and assertive, as she was on this occasion.