This is too funny.

How to Draw Manga: Girls' sex Life Illustration File TPB

This book pinpoints the specific qualities that make young horny women unique, like how their pants are inviting, the secret weapons they keep in their underwear, the way they sleep, and why they smell so darned good. Get the answers and many more with an intimate look at the sex lives of six very different young women.
All this time I have known I have been doing something wrong but I just wasn't sure what it was. I have no weapons in my underwear. That's got to be it.