Sensei?

Have you ever given a thought about the ambiguity in borders between some things?

Like, between friends and acquitances

Being spoiled and being selfish

Teasing and bullying

Taking a rest and slacking off

hmm, hmm

Swimsuit and underwear

hmm?

Chest and breasts

Ass and legs

The later half is a bit...?

For example...

Please take a look at these.