I interpreted it as a joke about how the kind of man that women tend to engage in these kinds of relationships with lack sophistication and maturity to the degree that they may as well be several children stacked on top of each other in a trench coat. Vincent is an uncomplicated, blank slate who is just happy to be taken cared of and given access to adult things. PC is so used to being actively treated like shit that she misinterprets this behavior as healthy and loving. She calls Vincent a “good listener” because he literally has nothing to say, as opposed to insulting, invalidating, or criticizing her.