In my wife's words:
This place is heaven for any girl who doesn't mind hanging out, literally. You will be warm - warm and dry or warm and wet, according to your preference. There is a LOT of wet here, including various temperature baths, sauna, mugwort tea that people pour over each other, the surprisingly chilly waterfall, and the many substances that get splashed on you as part of the scrub and moisturizing treatments. Did I mention olive oil? If you go for the full-body scrub (and don't bother going if you don't do this), prepare to be treated like prized, high-quality, well-marinated slab of steak. Never again ponder what to ask for as birthday and holiday presents -- just ask for money for a spa visit.