Romance Ambivalent is a term used by aromantic individuals to refer to the fact that they have mixed feelings towards romance. Romance ambivalence refers to anyone who does not fit into the categories or romance positive, indifferent, or repulsed. This could be for any number for reasons, common reasons being that one's feelings about romance change frequently, so they might be positive or indifferent one day and then repulsed the next. Their feelings on romance might also change based on the situation. For example, someone might be normally romance indifferent, but if they're in a non-romantic relationship and their partner is romantically attracted to them they might feel romance positive. The opposite might happen as well, someone could feel romance positive or indifferent normally, but if their partner is romantically attracted to them they might feel romance repulsed.
Romance ambivalence can also stem from internalized arophobia, which can make so the person doesn't know if they're actually romance positive or if any desires to have a romantic relationship are simply based on the fact that they feel that people should want to have a romantic relationship.
Not all romance ambivalent people are aromantic. There some alloromantic people who are ambivalent about the idea of romance as well.