Jack is a serial killer who meets Dio Brando and is transformed into a Zombie sent to fight the Joestar Group. He was inspired by the historical figure of the same name.

(Source: JoJo Wikia)

Beginning its tale in 19th century England, young aristocrat Jonathan Joestar finds himself locked in bitter rivalry with Dio Brando, a low-born boy who Jonathan's father took under his wing after the death of Dio's father. Discontent with his station in life, Dio's fathomless lust to reign over all eventually leads him to seek the supernatural powers of an ancient Aztec stone mask in the Joestar's possession—an artifact that will forever change the destiny of Dio and Jonathan for generations to come. 
 
Fifty years later, in 1938 New York City, Jonathan's grandson Joseph Joestar must take up his grandfather's mission and master the abilities necessary to destroy the stone mask and its immensely powerful creators who threaten humanity's very existence, the Pillar Men. 
(Source: Anime News Network)

__Non-Anime Roles:__ 
- Roadhog/Mako Rutledge (Overwatch)

__[Twitter](https://twitter.com/RealPaulStPeter)__

Héctor Gonzalo Moreno de Alba is a Mexican voice actor.

Young Jonathan Joestar’s life is forever changed when he meets his new adopted brother, Dio. For some reason, Dio has a smoldering grudge against him and derives pleasure from seeing him suffer. But every man has his limits, as Dio finds out. This is the beginning of a long and hateful relationship!
 
(Source: Viz Media)

Written and presented as the lost transcript of Dio's Diary, featured in Stone Ocean. In the book, he reflects upon his battles throughout the original series, describes his ideals and plans for "obtaining heaven" and talks about the concept of death, as well as his unfortunate mother.