On demand! Furthermore not showering doesn't necessarily imply no washing at all. Like with a sponge, washingcloth in maybe 4 minutes, like eyes, face, neck, armpits, crotch, feet?
You don't have to have cold showers everyday. I default to cold, and when grimy go for hot. You only really need to soap the places where the sun doesn't shine. And your hair doesn't need shampooing everyday. But each to their own.
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