Bed protector & sheets rounded corner

Before you purchase, and there is many places to purchase, accurately measure the width, length, size of the corner and depth with and without the topper.

A foam store is a good place to get the topper you want, they cut and trim to size. Some even put covers on the toppers.

Sheets are easy, but again, know the size and depth you want. You can ask someone with a sewing machine to cut and snip out the corner.