As a reader, I would assume that a Anime/Manga-style cover would suggest fiction that has that same "general feel" as the comics that are representative of the style.
Naked elf boys...not so much for me personally.
Starship Yamato, Speed Racer, Dirty Pair, Robotech, aliens and rayguns and starships and alien landscapes...I'm there in a heartbeat.
I also enjoy a lot of the DC2 covers over on Feedbooks...the authors are using comic book style art and writing superhero prose stories. Some of those stories get a TON of downloads.
If your audience is people who enjoy Anime/Manga style work, I would think this would be a good way to get their attention...the problem is distinguishing that this is a prose work and not a comic.