A sub category of pornography, in which a hot 9 is standing next to a plain 5. The plain looks of the 5 allows the 9 to transcend the barrier of being a 9 and attain the perfection of being a 10.
An extremely hot chick who becomes much less so when she begins to talk, revealing the inner workings (or lack thereof) of her pea sized brain. Not a problem for short term satisfaction but greatly reduces any chance of long-term relationships. A 9 to 5 sometimes shows uncanny knowledge in certain areas, such as the names of Brad and Angelina's kids or the price of designer handbags.
Bob: You see that chick I was talking to - she's smoking hot, but . . .
Ed: But what?
Bob: She thought Dick Cheney was a sort of necklace you wear on your pecker.
Ed: Total 9 to 5. You gonna try to bone her anyway?
Bob: Fuck yeah - I'm gonna show her my Dick Cheney!