An up-and-coming slaver writes a blockchains.  "SlaverCoin".  It's a fork of bitcoin, since bitcoin is the most well-known.

SlaverCoin

Consensus rule:  If you use nonhuman labor to mine sha256d, we get to enslave you.  Slaves must be given in proportion to traded coin, freely divisible.

SlaverCoin is a big hit.  Gets all the advertisements.  Everybody thinks it's a joke until people move in as servants when they buy coins.

Physical addressea are directly asssociated with crytographic addresses, so that the purchased and sold slaves know where to go.

A slavercoin kid discovers that non-slavercoin slaves are sharing their stories on other blockchains, and wants to try it out.

Meanwhile, on other blockchains, wealthy investors are getting a rise out of freeing slaves.

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