I would scroll right on by. A cover like the examples would suggest cartoons to me. I don't know anything about Anime or Manga, so to me its all the same, cartoons. I don't read or watch cartoons, kids or adult type. Just not my thing. So I wouldn't be interested if a book had a cover like that as that is what I would expect.
And if a cover like that is on a book with a total different genre, I would also not be inclined to look further. That means the author didn't represent the genre and so I wouldn't really trust the story either.
Reader expectations.
Other covers I despise are those that look like Sims characters. I see some of those on romance and other genres. Those tell me usually one thing, bad, really bad.
