Hey! It seems to me that the one who offered to help you with your question didn't quite get the heart of the matter and didn't give you an answer you wanted. So let me try and put my two cents in as well. I could bore you with a lot of text to read, but something tells me that the direction in which I'm about to go to explain it isn't quite close and interesting to you (maybe I'm wrong about you). So I'll do it as briefly as possible, and of course, in my signature style. I'm that one who's being on all characters' paths, in parallel and without exception, so I'm into Roxy in my own way either.
So, it's obvious there's something more in Roxy than just her lustful nympho nature and her behaving in a depraved manner. And she's not just letting the MC hang around with her. She's not just a hookup girl or a hot chick to fuck anymore, and the MC's no longer just her sex doll. The plot does thicken.
And a hard submission's definitely not what Roxy wished to get on that special date (you have been getting away with it, but the date's a major trigger to make a right decision). Not only the MC managed to conquer her body, but has been getting closer to her heart. She's much more sensitive than it might seem. At the MC's last training session, her sis Nat touches upon this issue, btw. In the near future, we will get opportunities to dive deeper into Roxy's life, into her past, into her thoughts and into her feelings. I'm sure she will be revealed from different angles. DreamNow will do his best.
So, in short, what I mean is that Roxy's not just a hot sex content in the story. And 'a good kick in his balls' shows us how bad the MC screwed up. It's pretty emotional. She's disappointed in him since she's forming an attachment. What I can see.
