On decorum when faced with kink

I can't be sure, but I suspect the eye mask a recent patient of mine brought from home was actually intended for BDSM activities. It was black leather, with fleecy lining on the interior eye patches and little straps on the exterior eye patches. All night I kept looking at it in wonderment. I considered making a veiled reference to confirm and so he knew that I knew, but decided to stay scrupulously professional.