The late 1800s were a time where a lot of shanghaiing was going on and the Neath strikes me as a terribly perfect place for that— Shanghaiing was the practice of just, abducting people to force them to be sailors, it happened a lot in the USA and England. They needed sailors and, well, you take a drunk guy out to sea and he doesn't have any choice but work or die.
The Neath offers a concerning possibility where a Surface sailor could abduct sailors, pass them off to a Neathly partner, and kill those who had been shanghai'd— trapping them not only in service at zee, but also eternally to the Neath... Imagine waking up after a drunken night to learn you were taken to the underworld, killed, and now had to zail on a zee of monsters with no hope of ever returning home.
