Umberto Eco and Dan Brown both played with the secrets hidden in the depths of libraries and archives in their books The Name of the Rose and Angels and Demons. I once visited a monastic archives in Switzerland that had the most amazing parquet floors—to protect them, visitors had to take off their shoes and put on slippers that wouldn’t scuff the fragile wood.
These slippers have a cable ribbing along the instep that just add to the cozy factor. They're toe up for maximum fit and yarn use, with a gusseted short row heel (done a little differently to prevent holes) and short leg. If you want a longer leg you may need more yarn.