Working hard all day and then get raped by your Dark Elf Overlord?
Sounds ok first, but is it really worth it?
A slave's life is worth as much as his production outcome. Your Overlord will do as they please with you. If you are really, really lucky, you might get to cum one day. And say goodbye to your honor, humilation is your new friend!
You don't get to be a slave by choice, anyway.