This is exactly what will happen if you don't wash your underwear.

Going Commando: Pros and Cons

Guide to Period Panties: How Period Underwear Works & How to Clean

An Ob-Gyn Weighs In on Whether or Not You Should Wear Underwear to Bed

Bloody Clean, laundry detergent

Is it okay to wear the same underwear for two days? - Quora

Bloody Clean, laundry detergent

5 ways to get rid of those stains on your underwear, because it happens to the best of usHelloGiggles

How to wash underwear to kill bacteria

Discharge and Underwear: Is Vaginal Discharge Staining Your Underwear?

Going Commando: What You Should Know Before You Do

What happens if you don't change your underwear every day?