The "Gio" in Giorno Giovanna's name is properly pronounced "Jo" in Italian. Also, "Gio" is close to his biological father's name, Dio Brando. Since most of Dio's body in part 3 was Jonathan Joestar's body, that makes Giorno a full human, and not a half-vampire.
This is the first official appearance of Giorno Giovanna. His stand, Golden Experence, is named after a Prince song, and is subtitled "Golden Wind" to avoid copyright infringement.
Leaky Eye Luka is named after a Susan Vega song titled Luka, about a physically and emotionally abused boy.