1. Hang a wood molding above the bed leaving space below to hang the cushion. 2. Apply some round metal hooks to the bottom of the molding where the cushion will hang. 3. Get a bench cushion and apply some fabric strips to tie it up. Hang it from the molding. 4. The molding serves also as a shelf.
This reminds me of thoughts I have had about a quilt headboard... (Having lived many years in earthquake country I am sensitive to the idea of anything heavy hanging over my head while I sleep... But a quilt should be safe!) We have a quilt hanging above above our bed. It is beautiful!