Bincho tan

Has all kinds of semi miraculous benefits attributed, but I would guess the main task here is to deodorise this personal space and help stop any smells generated in the little room next door from contaminating the rarefied sense of luxury and well being that so much work and care has gone into maintaining in the rest of the space you rented. A classy alternative to a diffused spray of Limonene.

(Oh yes, the smells might not just come from you, plumbing in Japan can be a bit disappointing, the stack of charcoal will also help stop unpleasant odours creeping in from the sewage pipes. MrLapLap tells me that charcoal is often used in dog mattresses)