After Shorter Wong leaves Chinatown in New York City, Su Rin steps in to take his place as Chinatown's gang boss. But Sin is still loyal to Shorter, and is not pleased that the Lee family is in cahoots with Papa Dino. "Our suits did a deal with Dino Golzine, but that's got nothing to do with us! I don't know what kind of shit they're planning, but we've got our own rules! And our boss is still Shorter Wong!" With these words, Su Rin convinces Alex and the remainders of Ash's gang to go to war against the unified forces of Dino Golzine and Daai Yan Lee.

Sin may be only fourteen years old, but don't let his looks fool you. He is extremely intelligent and cunning, as well as a skilled fighter. Ash is the only person who has ever survived Sin's attack with his deadly weapon, the "Flying Dragon Fang." Sin is also pretty arrogant, although he never hesitates to admit defeat when he feels that he has truly lost a battle.

(Source: boukenshin.net, HotaruKara)