Danny

Danny (ダニー) is a minor character appearing in Part I: Phantom Blood. Danny is Jonathan Joestar's dog and best friend in the early chapters of Part I.

Phantom Blood
Jonathan's father bought Danny, still a puppy at the time, when Jonathan was five years old. Danny was very afraid of unfamiliar places and strange people. Jonathan and Danny did not get along for a while, which caused Danny to bite Jonathan. Jonathan, in turn, attacked Danny by throwing stones at him. One day, while swimming in a river, Jonathan started drowning and was saved by Danny, which made them the best of friends.

When Dio Brando arrived, he kneed Danny in the jaw and later put him into a box, planning to incinerate the dog. Danny was burned to death and buried in the backyard of the Joestar Estate. That night, Jonathan cried while laying awake in bed, remembering Danny's death.

Steel Ball Run
Danny's Steel Ball Run counterpart is a white mouse raised by a young Johnny Joestar. At his brother Nicholas' suggestion, Johnny sets Danny free into the woods when his father orders him to kill it. However, Nicholas' horse becomes startled at practice and accidentally throws Nicholas off, killing him; the white mouse scurrying away into the woods is believed by Johnny to have been Danny.

During the Steel Ball Run, just as Funny Valentine is about to kill Johnny, he notices a white mouse nearby and becomes curious as to why a mouse would be drawn by Lucy's Stand's powers, before realizing that he is being drawn back when Lucy is taken by Gyro Zeppeli. It is unknown, however, whether the mouse was Danny or simply another white mouse that happened to be nearby.

Trivia

 * In the Anime it's skipped completely how Jonathan mets Danny and how Danny saves his life.
 * In the manga Danny manages to escape from the incinerator burning in flames to death, but in the anime this is only commented and not shown.