A couch top or slipcover is a removable fabric cover designed to fit over a sofa or couch, protecting the underlying upholstery from wear and tear. Couch tops can be made from a variety of materials, such as cotton, polyester, or linen, and come in a range of styles, patterns, and colors.

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If you can share even a sentence from the “paper” or where you saw it referenced, I can track it down or find the closest useful equivalent.

A "couch top" styling is incomplete without considering the wall space immediately above the sofa's backrest: