What if I lost to True Yorna? Will I have a different ending?
No, losing doesn't affect the ending directly.
So what should I do to change it? I don't know this game have multiple endings or not.
I know this is a really late reply but to get a slightly different ending you need to increase your lust level. Dunno how high you need to get it though.
As far as I remember it's just one scene that's different tbh.
