Not a Korean spa but I went to the Standard Spa on Miami Beach yesterday morning. I opted for the mud lounge where you get naked and slather yourself in mud then hang out to dry all while you are out on their yoga deck by the pool and water!!! I dropped my shorts while the attendant was still getting it ready and she was cool with me starting while she told me when she’ll be back to clean up.
I got hard rubbing the mud on my cock and it felt amazing out there. Several ppl passed by and saw me. I walked out on the deck so others near the pool could see me as well. they have a tub to soak Ac the end, and I stroked myself a bit more and shot into the tub (I was super horny!!)