HEARTBURN.

"WHAT THE HELL IS GOING ON? WHENEVER I RISK MY LIFE FOR THESE PEOPLE, SOME WEIRD FEELING WELLS UP INSIDE ME... LIKE COURAGE... THEN MY HEART STARTS TO... TO... BURN... AND I THINK... NO, I KNOW I CAN DO ANYTHING...!"
-kikuchi katsumi.

When a 9-year-old girl named Kikuchi Katsumi is born with a stand named Primadonna Girl, lives in Naples, Italy, and is drawn to a kid named Haruno Shiobana just because of the simple fact that they're both Japanese become good friends who do everything together- it's no surprise that at least one of them gains feelings for the other.

And Haruno Shiobana is the one who gains these feelings.
But he believes that these same feelings are nothing but an annoyance, and continues to stay at Kikuchi's side, never once mentioning it to her at all.

But as the more the two age, the more corrupted their beloved Italy gets. And soon, they're beginning to see the heavy impact the Neopolitan Mafia has on the world around them. Even though they're young children (11 years old), the two aren't ignorant of the suffering of the people of Naples.
And of course, the corruption of their beloved Naples upsets the two.

But it especially upsets Shiobana. Which marks the start of his golden dream.

A few years later, Haruno Shiobana decides to change his name to Giorno Giovanna, and then he meets a man named Leaky Eye Luka, who comes to him for the sole purpose of money. After being denied such, Luka gets upset and attacks Giorno, which returns the attack to him, leaving him fatally injured. All while Kikuchi is watching, dumbfounded about the fact that her best friend has the same kind of ability as her.
Then they meet a strange man named Bruno Bucciarati, who follows them because they unintentionally killed Leaky Eye Luka. The three come to an agreement, and now, Kikuchi and Giorno are tied up with gangs, the mafia, and most importantly, stands.

But Giovanna has another golden dream, and that is marrying Kikuchi Katsumi.