@IronRaven I apologize, I misunderstood you at first. It's just that the game already has so much bad content for Astarion, the video with the evil ending, where Tav brings him to his knees is really painful to watch, and the ending for the evil DU was made so that now for me personally the possibility of playing as a DU without rejecting Bhaal is just destroyed by that ending. Even in a romantic scene, where you can't discuss the topic of “humiliating yourself” in any way, there's such a disgusting “option” as “kick him in the balls”, which causes a flurry of negative emotions on first playthrough and a desire to finally force myself to start understanding the game code at least a little bit to find out if it's possible to cleanse my own game of that text, on subsequent playthroughs/replays of that scene. But the way in which you explain this possibility of domination is certainly another matter, if one believes that the developers can somehow adequately implement it.
About Astarion's dominance over DU, that requires some sort of “internal roleplay” to explain it for yourself. I like several variations for such a roleplay. One, the DU is showing care for Astarion in this way, not “degrading herself” but elevating him, thus helping him to heal the trauma, to feel “on top”, to feel in control and safe, which allows Astarion to open up sexually, to really enjoy it, and to trust his partner when the DU shows him acceptance and gives him the opportunity for dominance and control. Second, the DU thus shows those around him how to treat the Lord in this way. For example, Wyll (if he is alive in this playthrough), calls Astarion a “degenerate”, flies into a wall (or something else along those lines, various spells can be cast on companions), then the DU kisses Astarion on her knees, and when she gets up, Wyll goes flying again to cement it.
Third, the DU can be obsessed by Astarion and enjoy everything he does, which in no way prevents the DU from behaving dominantly and aggressively towards everyone else, because only Astarion is the object of their obsession and their attitude towards him is radically different from that of the world at large. Suitable for a somewhat insane Joker-style DU. The DU can show everyone who is really the top predator here, it's just that this predator only allows one person in the world to do whatever he wants.
