I am gonna start offering a lining option for the bodysuits, boxers, pants, etc etc.

lining material options would be probably just spandex. because of how soft it is and its breathing yays. Fleece with a heat warning would be another. (fleece + fur, ur gonna heat up..., it be fine for boxers and pants. full suit..might be a bit much for fleece)
other thoughts were silk and velvet.