‘Help! My New Girlfriend Doesn’t Wear Undies – Plz Adivse

We are getting along well with this new girl, but she doesn’t want to wear undergarments. She wears jeans without pants and shirts or blouses without bras. On, could you kindly provide me any advice on how to fix this?
shirts sans bra
Despite wearing tite in her skirts, she wears trousers without pants.