With multiple characters on the same account, you *know* that all those characters are played by the same person. So when Kepler is harassing you and being mean, you know that when Keplerina starts trying to sweet talk you, it's really *the same person* trying to work you from both sides. You won't be lulled into confiding your secret plans to depose Kepler. But if the supposed friend comes from a completely different family, there is a possibility that the person really is a friend, and wants to help. Sure, they *could* be a plant try to trap you, but they could also very well really be a true friend. A multi can take advantage of this anonymity to worm their way into your confidence using all their knowledge to bait you into believing whatever they want, and then screw you over.
A multi is, plain and simple, a liar through-and-through. It is someone metagaming in order to gain unfair advantage.
