It looks like a very well made wallpaper at first, but on a closer look, it has a few flaws.
For one thing, the background seems really blurry, and the grassy area where the characters are take up too much space without actually being anything there. It's like an empty space with some green paint over it which is painfully deserted for an outdoor wall. You should have used more colors to make it more pleasant to look at, and also use lighting with shadows. Which brings up the second problem.
The characters on this wall don't blend into the BG. Not one bit. They are much too clean for a visibly not as good BG, their pose don't match the place, and they just kind of look like they have been taken there from a vector art with no real editing behind it. When you're making a vectored wall, you have to make sure all the elements of it are on a high level for it to look good, because a vectored wall is all about the details and I can't see it here. Sorry to say, but as I see it, pretty much everything that should be there is missing from this wallpaper. Still a nice addition nonetheless.