“Bendito entre todas las mujeres” is a play on the well-known phrase of the Hail Mary prayer:
Hail Mary, full of grace,
the Lord is with thee;
blessed art thou amongst women,
and blessed is the fruit of thy womb, Jesus.
(Of course, in Spanish the prayer says “Bendita entre todas las mujeres”, with bendita in the feminine.) It is often employed as a joke when a man is found in a gathering otherwise consisting of women only. It can be employed by the man himself or someone else, but always in a playful way. It sometimes suggests that the presence of a man is unexpected in such gatherings because of usual gender roles and customs. It actually says nothing about the women themselves (whether they're beautiful, or charming, or welcoming), or about how the man feels. It merely points out that the odd one out in an all-women gathering is the man.
For example, yesterday I found myself for a while bendito entre todas las mujeres in a booklet binding workshop (until another man arrived). And in an administrative office where I worked, I was frequently pointed out as bendito entre todas las mujeres because I had no male colleagues.