You are right Miguel, they are beautiful.
Since he is using his favorite models he seems to have gotten to know them so well that he captures their thoughts.
You wonder what they are thinking about, and they are so "normal". Nothing fancy or pretentious, just girls being girls., and they seen to not mind so much attention so there does not appear to be any shyness in their expressions.

Thank you for your wonderful comments, Joyce. Yes, Bouguereau was a genius who not only painted extraordinarily well but also captured his portrayed girl's thoughts seemingly without much effort, which places him among the finest portraitists to have ever existed. You have made such an important point there.

This is very lovely. It almost looks like a different artists' work-a totally different perspective. Simple and detailed.

Miguel,

Luis, you're focusing on one of the very rare arts!