In the item shop, in the far corner of the personal hygiene area, there's a selection of shampoo that contains only natural ingredients, none of that chemical nonsense. There's a few options, but I've had best results with the pink bottle. Rather than coat the hair it enhances the natural health and beauty of it, which means that it stays clean for a longer period of time.

It works best in a lukewarm shower, air-dried, with only the tips conditioned.

[There is a pause, and then:]

If you find it, don't take all of the bottles or I'll kill you.