Um..whatever. There is no shortage of books sold by amazon that feature male-on-male rape: Mysterious Skin, Drowning Tucson, Deliverance, Last Exit to Brooklyn--Need I go on? so maybe it's your publisher sucking or something. Amazon will sell anything. Even sex toys. So whatever.
If Amazon is engaging in censorship, good. This country could use more censorship, not less, and since Amazon is not the government nor affiliated with the government, there's no First Amendment. It's a shame that Amazon's new-found discretion didn't extend to the how-to child molesting guide it published (and briefly defended) a few months ago, but I guess you have to start somewhere.
You seem upset about what you think is a downside of freedom. Censorship? You really think that's a good thing? We all still have the freedom to buy or not to buy and that's the only thing that matters. Your viewpoint seems astoundingly un-American.