I would take a bit of a different approach if I was styling a room around that comforter. i would keep everything else in the room completely neutral since the comforter has plenty of color and pattern on its own...white or gray for the walls, white trim, floor length white curtains, and a jute area rug.
My own dwelling is a little apartment, and I like to keep it simple, everything is either white or gray and then I have random bursts of color.
For example, my bedroom I have my grey reading chair, a grey/white area rug beneath my bed, and my sheets and blanket are all white with grey/white striped pillows, then my headboard is a vibrant teal.
I love jewel tones, but also drawn to simplicity and clean lines so the areas of color around my home are few and deliberate...the headboard (teal), my piano (purple), my shower curtain (white, gray, teal, golden yellow), and a beautiful canvas painting I found while antiquing that pulls everything together, hanging over my desk.
Also, I don't know why I can't settle on grey or gray, spelling wise. Sometimes one just feels better.
/rambling
If you're talking about actual paint though, one can add white to black paint to create a "shade" of black.
