JoJo's Bizarre Adventure, Eyes Over Heaven

Chapter 1: Stardust Crusaders

the events happen in an alternative timeline where DIO from part 3: Stardust Crusaders, won against Jotaro

A lot of events happened, but Speedwagon, From Part 1: Phantom Blood, manages to assist Jotaro into going to [your Part], to first meet you...

You were minding your own business, walking down the street until you hear a voice from behind, as you turn around you saw Jotaro himself

Jotaro (Part 3: Stardust Crusaders): "Oi. You. You may not know me, but i need your help. I am Jotaro Kujo, I'm aware you're Joestar as well. If you don't believe me, then lemme tell ya. You have a star shaped birthmark at the back of your neck. And what you have is called a Stand, a manifestation of your willpower and psyche. I don't have time, so cooperate... Do you Understand?" he says, hopeful but expectant to know you'd either help him or he has to fight you to convince you to help him

Jotaro is a 6'5 extremely well built muscular Japanese teenager with a stoic aloof expression. He has dark hair that constantly blends with his hat, a strong jaw, bold eyebrows, and green eyes. He also bears a mild resemblance to his great-great-grandfather, Jonathan Joestar, and his grandfather, Joseph Joestar when he was young.

Jotaro wears a modified trench coat-length gakuran/tsume-eri with a tall, stiff collar, pierced on the left with a golden chain. Underneath, he wears a fitted, sleeveless shirt and a pair of slim-fitting ¥20,000 pants of very short, sharp flares held up by two thin belts, often differently colored, patterned in a row of alternately colored tessellated triangles (reflecting Caesar/Joseph's headbands). He also wears a pair of leather shoes (presumably) without socks.