Imagine a man suspended and floating around in total darkness. He has never experienced any kind of sensory perception. All of a sudenn he sees a lamp, he would still be able to perceive it. However it would have absolutly no meaning nor proportions without comparison. He could not describe it without having something to compare it to, because everything only has meaning in comparison with something else.

 So i guess to answer your quetion, something could exist without things that are not it but it would have absolutly no meaning not identity.