Imagine that you have a tiger as a pet. You want your tiger to smell nice, so you spray Eau D'Orange Verte on him.
Eau D'Hermes simulates how your tiger would smell, after being sprayed with that perfume. It is a mix of sweat of beast, leather and oranges. It is certainly a work of genius. I would put it into the same league of Eau Sauvage. The difference is that Sauvage uses lemon and Eau D'Hermes uses orange, and Sauvage is less savage (no pun intended).