It was OK if there was a big public bathroom or a family bath below.
Bathing normally 🆗 And after reconfirming by phone, I was allowed to go.
There was no problem because it is a private bath.
There is no public bath. It was a unit bus.
I did not specifically prohibit tattoos.
Tattoo principle is prohibited in large public bath. You can not hide it with a sticker etc.