The Cumminsville Killer, also known as the Cumminsville Ripper, the Slouch Hat Man and the Man Gorilla, was an unidentified serial killer who is believed to have claimed five victims in the Cumminsville neighborhood of Cincinnati, Ohio, United States, between 1904 and 1910. In recent years, theories have surfaced tying the murders in Cumminsville to the Dayton Strangler, another unidentified serial killer believed to have been active in Dayton, Ohio, from 1900 to 1909.