How Lae'zel romance works?

So i am at my third playthrough and this time i was planning on romancing Lae'zel, he scene proc'ed before the tiefling party, and now at the tiefling party, i was in doubt about getting Karlach scene since i can't get Lae'zel again, (Fun fact: i discovered i was in a romance with gale and don't even know when it started).

But my doubt is, i never ever got Lae'zel romance scene, like, never, and in all my playthrough i have the one night with her, but never was a scene where she ask me or sugest going futher, like, not even the fighting scene i got, so i never got the chance to turn her down after that and was thinking, if i sleep with any other character, does lae'zel simply lock out?