In one of the assassin quests, you are hired to kill a couple of spies. Well, they are not homeless. They have an owner, and he doesn't like when someone messes with his property. So, if you kill them, you get a reward and a pat on the back from the assassins' guildmaster, but your reputation with the faction that has a fondness for spying just dropped by 10 points. Keep pissing them off, and soon you'll be the one fighting assassins off. On the other hand, you can protect the spies and make new friends, but your career with the assassins guild is now completely over.

What I'm trying to say is when you are asked to do something "unto" another person, remember the Bible and take a moment to think who this person is and how your actions might bite you in the ass, because most likely, they will.
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