Sitting on a temporary stage against the backdrop of a wall painting of Mount Fuji, American musician Jim O'Rourke is playing his guitar and singing softly.
It is early December, and his audience of men and women, mostly in their 20s and 30s, is soaking up the atmosphere.
Soaking is the operative word because the musical experience they are enjoying is called "furo (bath) rock" at the Bentenyu "sento" (public bathhouse in) Kichijoji, western Tokyo.