It's pretty safe to say that it's an uncommon practice, but not unheard of based on the examples before this post. From the start of this game, I've played an escaped slave, as well as built an FC based on my character's personal backstory (the former slave hold is now a sanctuary for escaped slaves and those who wish to help them). But in general, there are elements of slavers and slavery within quest lines, both main story and class.
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