There was a lot of trust and love here (and quite a bit of kinky pain), but I'm glad that the importance of that flashback came across. Xander, our original Xander, had and hid this kink, so for him to enjoy it now is not a perverted leftover from his days with Leshar, it's him overcoming the fear of what Leshar did enough to go back to enjoying a little pain mixed in with his pleasure.