You don't. Getting that ending with Khulan gets you a true game over that returns you to the title screen. And although Khulan is for me by far the worst girl in all aspects (not a fan of the stupid jock personality, her kicks is the only foot related animation in the game turning me off, and even fetish wise cannibalism and amputation isn't really my cup of tea) I did enjoy reading that ending precisely because you submitted so thoroughly.
I really hope that other girls get the true game over mechanic. For me Lily is the best girl and I think Cobra is second because I'm a sucker for the level drain mechanic, but really, apart from Khulan all women have been amazing, so I find it kinda frustrating that none of the other women have an ending where you really forget about anything else and focus only on them. For instance even after Elisa supposedly completely mindbreaks you, you never even think of attacking Aarav for betraying and insulting the most important person in the world for you (I know you need the shop, but he could have just left for real and Howard could have picked up his belongings or something).
And after that dream sequence Lily my first thought was can I get this ending for real? I sure hope that she gets an expansion where you get a game over because you are so smitten with her that even if you could just straight up climb the tower without any of the other bosses preventing you from releasing your friends, you wouldn't do so since leaving her side even for a minute for any reason that wouldn't be to her benefit or pleasure would simply be absurd to you.
