Or, perhaps something closer to what you are asking, this is a great Korean style spa - separate sections for men and women - male nudity was the norm when I visited about three years ago - maybe there are some locals who have visited more recently?
It was a great, relaxing place to hang out naked for a couple of hours enjoying the spa, sauna, showers, etc. Also very low cost for the standard of the place - I think only $20 - more if you want massage or other treatments.
IMPERIAL DAY SPA