It turns out that in Japan there is a long tradition of masking the noises made when using the toilet, and the lineage of this device goes back as far as the 19th century. The first of its kind was a big bronze urn filled with water, called Otokeshi-no Tsubo — “urn that covers sound”. To create the masking effect, a plug would be raised from the top of the urn, allowing a stream of water to rush out of the dragon’s mouth below. But it was only high-ranking officials who could enjoy this luxury.