Rustic charm and basic. Like a beach house that has been left unused for a couple of months (I'm talking about the decor and fixture). Don't get me wrong, my room, bed and toilets are clean and well dusted. The staff are very helpfull and welcoming. Nothing to complain about my stay. It's just a tiny bit low on the price vs quality curve, especially against other riads that I stayed in Morocco.
Essaouira is literally next to the sea. If your room is not air conditioned, expect dampness and humidity.
All in all, I would stay again.