They know she won’t break from torture so they make it so she gives into pleasure. From what I remember Neimilia plants a curse on her that causes her to feel pleasure whenever Raidorl speaks to her. Kinda rapey, ik, but from as far as I’ve read he never lays a hand on her. It’s simply to break down her pride as a loyal servant of the kingdom and make her their puppet for information which was pretty satisfying imo.
Other than this incident he’s very cautious towards the kingdom and pulls some crazy shit so that the kingdom can’t backstab him, fortunately no damsel in distress either