The Slave Factory

Slave factories, a crucial but largely forgotten part of the slave trade, were bases on the African coast that existed to buy slaves and resell them to slaving ships. They were places of notorious suffering and exploitation, detested by both the natives and by white slavers.
This story, in 12 brief chapters, focuses on the intersection of lives at one slave factory, Porto de Maria. Diego, its boss, is jaded. Matthew, its resident priest, has a terrible secret that drove him to Africa. Bowlu, his slave, struggles to find recompense for what he's lost. William, the ageing captain of a visiting slaving ship, commands a divided crew, worries about interdiction at sea, and has come to Porto de Maria to determine his future. When these lives cross on the eve of the American Civil War, none of them will remain the same.
From Martian Lit.