Such as the horrible Jester quest where he tells you a joke and you pretend to laugh, or "Sebastian of the Celestial Cards"
When someone interacts with those, it always makes it very difficult to see what's happening.
If it's possible, maybe make those conversations "invisible" to anyone other than the talker, or just make sure they won't be in the middle of ticker square or the open door.
edit: ...just so nobody takes offense. "horrible jester quest" meant the JESTER is horrible, not the quest.