Your explanation perfectly match my understanding of their relationship. However, that is exactly why I've asked the question about her IRL prototype. Speaking directly, I have the doubts that such human does exist.
At the same time, I have too good self-control to be distracted by more trivial thoughts about VN's character. And "years of experience" to boot. Thus, I repeat myself and others here, that CH is the novel at first, visual at second, and adult at third place only. And it is second to none!