- Have you kissed her at any point before getting that dialogue?
- Also which race are you playing?
I believe to get that dialogue you have to fail a hidden saving throw against poison when she's kissed for the very first time (similarly to how Shadowheart can only trigger a saving throw against wolves once per wolf), but I'm not entirely sure because I actually never managed to get it in my playthroughs.
Playing as a darge urge customised to a wooden female elf (not half elf) character and as soon as kissing was introduced for Minthara in hotfix 17, always give her dozens upon dozens kisses each time I play, so I must have kissed her like over 20 times in a single constant game of Act 3 before this was triggered (not first kiss by far) for me the first time, maybe noteworthy to mention the last "fog of war" I had left to explore was the abandoned plague ship and afterwards I went back to elfsong tavern camp.
This now just confusing to me because the very first time I kissed her either I succeeded the saving throw or you are given more chances in hopes of failing this saving throw again?
I just hope its not buggy where as, the games treats it as triggered event despite reloading to an earlier point.
