If you're asking about underwear, have you heard of chamois butter?
One big reason to not wear underwear with your padded cycling shorts is to avoid chafing and pressure from the seams and elastic around the legs, not to mention if the underwear ends up folded or wrinkled between the chamois (bike shorts padding) and your tender bottom. Chamois cream or chamois butter is a product used to put directly on your bottom or your chamois (or both) depending on your preference. It is nice. This type of product reduces friction between your bottom and the chamois, reducing irritation.I think using chamois cream with underwear would be yuckky. Get those soggy bike shorts off as soon as you can after a ride to avoid developing "saddle sores" or other discomforts which thrive in a warm moist environment. Tokie