This is great. It reminds me of a TV series or perhaps a film (maybe it's Tommy Tricker and the Stamp Traveller) where a boy travels using a stamp (he somehow entered inside a stamp and could post himself to where-ever he likes. Anyhow if I recall correctly he became like a drawing inside. And the background of this drawing creates this contrast as if the child is out of place or he can move from there it's only a temporary position for him.
In short: loved the background and the game between it and the pencil colours.