U know what I'm thinking?

Have you ever experienced, talking to someone who doesn't know you that well, yet he's able to know what you are actually thinking, better than some of your closer friends? Well, I know one such person, and his name is Aaron (though this Aaron must be in no way thought to be the same as the one named below, as they are total opposites). Sometimes, when I talk to him, I have different meanings in what I say, things that usually people don't realize. Somehow, he does. And it's scary sometimes. You know, when I don't really mean for him to know what I'm thinking...