Sex lies

Dude # 1: Last night, I screwed her brains out, she was loving it.
Dude # 2: *High Five*
Girl #1: Oh really?
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Girl #1: Did you really have sex with him last night?
Girl #2: Sick, no! I bet you could practically braid his back hair.
Girl #1: Hmm.


Why do people feel the need to lie about people they have had sex with? I'm not saying in this scenario that the girl lied, I'm saying the boy lied. But it goes either way. I've had girls and guys lie to me about who they've had sex with.
First off, why go to the lenght of lying about who you had sex with? Why make up a fake story and date of when this happened? Most of the time, these liars bring up the story all on their own, it isnt prompted to them. So they must of thought of this story and thought of who they could tell and thought of what they could gain by telling this story. But what are you gaining by lying about this?
Secondly, the people always tell people that are friends with the said person they had sex with it. So naturally, if you lied about it, the friend is going to figure out and the said person is going to find out you're telling people you had sex with them.
Case in point: During junior year, a friend of mine went around telling people we had sex. Clearly I was virgin then...I wasn't boning anyone. So almost a year later, I find out he has told all of these people that we had sex, outraged I call him. And what do you think happens when I ask him about it? He lies and says he has no idea what people are talking about, but hmm... funny, several people told me. I don't care anymore that was a long time ago, but still... he lied about it originally and then lied to me about. I would have been happier if he just admitted to it and apologized.
So why are you lying? What are you getting out of this? When you tell me person after person that you've had sex with, I don't think you're this awesome person. I'm not like, "SHIT, people must really like you, you must be really attractive, WOW...you're awesome." I don't care what you're number is, unless youre a boy, cus I dont want syphillis.
I'm more than willing to listen to funny sex stories and some crazy thing that boy did last night, like trying to give you a rim job or something, but if its all lies, I dont want to hear it.
Most of the time, by the end of the conversation I know if you just lied to me. Or I go make one phone call and I found out the truth, if it seemed fishy. Basically, what I'm saying is, if you ever lied to me about someone you had sex with and you wanted some sort of recognition for it, I hope I didn't give it to you and that I know and I went and told everyone that you told, that it wasnt true. Because thats the kind of bitch I am. So stop lying for goodness sakes. Spend your time getting laid not making up stories about how you got laid. Dumbass.