It seems there is no problem with the background . I never experienced anything like this . My friend suggested me to darken the color or shade background or character.
I think would be more interesting if you more focused to demon , so even if you feel unattractive background , it does not matter anymore , because of the background that you create feel a bit abstract .
Try to darken the color of his character , but be careful not too dark , because the skin color you use is quite dark . For the eyes I love , wild impression was , it does not need to be changed again .
On my oppinion, your art give me sense myth demon from urban folklore.