Jack the Ripper is an antagonist featured in Part I: Phantom Blood. He was inspired by the historical character who still remains a mystery today.

Jack the Ripper is shown to have a gentlemanly facade, able to convince a woman to walk with him on a dark night. When he reveals his true colors, he does not hesitate to stab the unarmed woman to death. As a vampire, this trait becomes even worse, as he is able to produce knives from his body and is shown to have a desire only to cut things and cause pain.

Jack the Ripper, after killing what was presumably his last victim in reality, was selected by a then-incapacitated Dio Brando to become one of his vampire minions.

Later, he is injured by William Antonio Zeppeli when he demonstrates his ripple and finally eliminated by Jonathan Joestar.