No self respecting JW would doubt the demons ability to attach themselves to physical objects. For example if a JW put a poster on their wall of a pentagram or some other "satanic symbol" that's a "doorway" for the demunz. It's inviting them into your home. Your going to have one come sit on your chest making it impossible to breathe until you can yell Jehover and make it flee. Or your going to have doors open unexplained and things fall off countertops. But, the elders could come over and pray and you could throw out the bad picture and be okay.
So I know some in here still are fundamental Christians. Here is the question.
What about your computer? If you had looked at pentagrams and other devil stuff online then a copy is stored on your hard drive for a while. Can the demons enter through the copy on your hard drive? Or what if you saved the picture purposefully on your hard drive and made it your screen saver? Or does the fact that it involves digital and electronic technology keep them at bay?