Plain, white colored panties. Sometimes they may also be accessorized with a tiny red bow on top as mostly seen in anime.
In Japan, white panties are seen as very cute and/or sexy for a woman to wear and, in most cases, white panties is mostly seen as the driving force of ecchi and hentai art. This is in contrast to America where it is considered to be childish and silly for a woman, even a teenager nowadays, to wear them, since they are typically worn by little girls.
