"Alright. So let's go back a while back on Earth...A meteorite hit somewhere in Iceland or Greenland or something, anyways it carried a virus intent on killing human life and people died when they got near it. However due to evolution some Humans adapted to said Virus and could develop a Stand, so some guy made 6 arrows out of said meteorite, a Mob Boss by the name of Diavolo stole all six and supposedly sold 5 and kept one to himself to an old Lady by the name of Enya Gail the Hag. Then Enya gave away all the arrows due to something..I can't remember on that. Anyways I got hit by one of them and I developed a Stand, which is the guy you saw earlier." He explained the history of the Arrow. "Now anything can theoretically develop a Stand, even a Tree or Dog. Don't ask me how or why, it just can. It is literally your Psychological and Emotional manifestation, so if it gets hit so does the user. Same goes the other way around."