Now, nowhere on the cover does it confess that this is a "sprawling erotic thriller." There are no naked people on the cover (in that tiny depiction of the dude ninja and the woman, it looks more like he's killing her, right). There is no genre indication at all. So imagine how surprised this kid was when he sat down and read about ... er, ninjas? Really smoochy ninjas? Which was totally not what he was expecting.
This is the exact kind of horror and betrayal readers experience when publishers attempt to market broadly and lose sight of their actual audience. The people who do buy the book stand a good chance of being mildly squicked at best, furious at worst. And what do you think that does to their future buying decisions? Do you imagine those people who have been once betrayed will blithely trust again? Do you think the adorable anime-ninja aficionado teen is ever going to buy a likely-looking book at the bookstore without at least three friends confirming the ninja-focus of said book?
Pro'ly not. So people, please stop doing this, even if it seems like a clever or creative way to attack the market. It might get you a few sales in the short term, but it will lose you readers in the end.
And yes, I know there is a little bit of irony in me coming at you with this advice, since my book covers strongly indicate kickass-heroine urban fantasy when the stories inside are... (oh god, not sprawling erotic thrillers?). Well, whatever they are, they aren't urban fantasy and are unlikely to appeal to the average Ilona Andrews fan. Oopsie. My excuse -- and it ain't a good one -- is that I didn't understand markets when those books came out.
I promise to do better. So should we all.
And also, in case you're worried about that teenage boy, you needn't. He came through it, even though, sadly, he never became Japanese. He grew up and married somebody who has written... wait for it ... omg yes, sort of sweeping science fictiony erotic thrillers. And worse, she makes him read them. (I'm really sorry, honey.)