Pathfinder: Wrath of the Righteous ran into a game-breaking bug if certain circumstances are met. However, it's easy enough to walk around, provided you didn't trigger it already.
Owlcat Games announced that there is a major bug in Pathfinder: Wrath of the Righteous , involving Act 5 and romances with either Daeran or Sosiel. Beware of potential mild spoilers if you haven't reached this point of the game yet but it shouldn't affect your experience too much even if you read the entirety of this article.
Namely, at the start of Act 5, you can go back to Midnight Fane after you figure out what to do with your mythic powers. This is the part that can break your save if you romanced Daeran or Sosiel. It only occurs if you bring these companions into the area and only if you had a romance with them triggered.
Therefore, the easiest way to avoid the issue is to not bring Sosiel or Daeran there and considering there is no major threat inside, you are probably not going to feel the lack of healers in your party. While easy to avoid, we would once again stress that you should avoid bringing romanced Sosiel or Daeran to Midnight Fane in Act 5 for the time being - it will irreversibly break your playthrough that may have taken over 100 hours thus far.
Owlcat Games are expecting the fix to arrive in patch 1.0.6, which is due at some point during the week of September 27, 2021. It will fix the bug but not broken saves so tread carefully.