Glimpse of Panties in Japanese Anime, Innocent?

in Japanese cartoon (anime), you can always get a glimpse of panties.

Seemingly innocent exposure. But it's ALWAYS there!

In real life, exposure, is the function of skirt. The exposure is often subtle, either by intention or by feigned accident (a controlled lack of diligence).

you can see such exposure in a clip of the movie Trainspotting, when Renton meets Diane. Bedrock - For What You Dream Of (Trainspotting). When a female does that, it signifies sexual invitation, usually to a single male.