Answer by  
                                                                                          DiggityDoo (100)
                                                            
                          
                          
                                                           You don't want to add any additional colors, since you have your accent color already. I would suggest large framed prints of black and white posters, such as Aubrey Beardsley illustrations, or some b/w photographs. Use black frames on the red wall, red frames on the black wall.