The case described in part 1 is not rape, but it’s still a form of… enslavement, I suppose. Still terrible in its own right. And then there’s the case in part 2, in which the power dynamic is so skewed that it’s considered rape pretty much by default. That also ties in with emotional abuse, which I’ve compared this to before.
So yeah, I agree, both of these cases are in play as useful analogies when it comes to Heartbreaker.