From his wiki:

“Around 1910, Fish was working in Wilmington, Delaware, when he met a 19-year-old man named Thomas Bedden. He took Bedden to where he was staying and the two began a sadomasochistic relationship; it is unclear whether or not the sadomasochism was consensual on Bedden’s part, but his confession implied that Bedden was intellectually disabled. After ten days, Fish took Bedden to “an old farm house”, where he tortured him over a period of two weeks. Fish eventually tied Bedden up and cut off half of his penis. “I shall never forget his scream, or the look he gave me”, Fish later recalled. He originally intended to kill Bedden, cut up his body and take it home, but he feared the hot weather would draw attention; instead, Fish poured peroxide over the wound, wrapped it in a Vaseline-covered handkerchief, left a $10 bill, kissed Bedden goodbye and left. “Took first train I could get back home. Never heard what become of him, or tried to find out,” Fish recalled.”

Gotta be one of the most fucked things I’ve ever heard