Android: What kind of explicit content is not allowed on Google Play?

I know that obviously explicit nudity is not allowed on Google Play. But what exactly is nudity in its sense? Is it just the explicit appearance of the nipples and vagina of the breasts, or does it also imply the appearance of the lower "line" of a person?

I'm asking this question as there is an application that sells lingerie that has been removed from Google Play for explicit content because the models (therefore, the photos in the application) were of girls who wore lingerie and some of the clothes were " sexy". "some.

So I was wondering: what defines the explicit content of nudes?

Any source of links would be greatly appreciated.