What is this anime where a poor girl forced is to wash an ugly guest that's very muddy? I remember a scene from an anime which I can't identify. (I don't remember whether it was a film or a series.) It was in the style of The Girl Who Leapt Through Time. I watched it about 3-10 years ago but it could be much older.

What I remember: A poor girl works in a public bath and is forced to wash a special guest who the other girls working there don't want to wash. The guest is coated in mud. The girl gets help (maybe animals?) / a special soap. She uses the soap on the customer and the mud vanishes. As a thank-you she gets a reward. I think I could see gold coins in this scene.

I already went through the list of anime I remember watching but it was none of them. As this scene regularly comes to my mind, it annoys me not to know where it's from.
This is presumably the scene from Spirited Away where Sen has to clean the river spirit. (here's a crappy camrip on Youtube)