Not all of them.
Some are smooth skinned, some are sandpapery.
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Esme Weatherwax I swear on my tash it's daycent hash, Wed 3 Jun 2009, 10:45,
archived)
That would be the smooth skined sharks.
Also, not all sharks have heads that are shaped like hammers, but they are shit at bashing in nails.
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turb0t, Wed 3 Jun 2009, 10:50,
archived)