umm... all of this are in your bedroom? well.. if you are set with all these pieces, pls do not stuff a leather chair in there, let alone a brown one. white wooden chair (think nordic!) would be ok as you have so many trinkets in one room already. anything else would make it more dizzy. but your overriding tone here is black and white and with IKEA pieces there (i actually like them) you need to keep it consistent. i know you stated you do not want to change any existing furniture. but would not a simple and not so expensive IKEA desk be much better than that "office depot" one you have right now? as for wall paper around the window? no need.

Thanks Tia! I agree about the desk. I just don't want to spend too much on this room so I'll think about switching it out. My bed is actually a green color like this, which is why I was thinking a small brown leather chair might look good with these tones. White could be good too!

This black and white wallpaper would look pretty awesome there