Through linen lockers long must rummage,
Haul out with hands the household bedding
and find on the level of the flannel pillowcases a thin package with katakana on it, and inside a scratchy washcloth. It's what the Woad Song calls 'a brilliant blue' which clashes mightily with my pink and grey bathroom.
And on the package's side these words appear: haado taipu. So now you know.
(It's a brand unknown to me called water color, in romaji, with precise instructions how to use- start at the feet and work up, don't rub so hard as to harm the skin, nado nado.)