my sister is pretty gross with hers too. she like never pays attention to the warning signs and so pretty much all of her undies are bloodstained. my mom tried to give them to me bc my sister got too big for them and i was like, 1) these are two sizes too big and 2), i'm not going to be caught dead wearing these
for real tho she needs to shower more (or see a doctor for a smell that bad) or at least spray some air freshener or perfume down there. it's what i do on the odd day that that place decides to smell a bit bc there really isn't a way to make it stop, you just gotta freshen it up and wait it out pretty much.