You book a room there. You don't have to wear clothing inside. Outside of the room, e.g. when going to the bathroom you are expected to wear a robe at least.
No clothing required,you get a private room with jacuzzi and maybe steam room plus Japanese garden with a fountain and a pot of delicious 🍵 tea.TAKE my word for it and book Room#3 it's well worth it,take me +it's 1/2off
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