Duo Lon/Story

Past
He is a member of the assassin group, the Hizoku clan, and the half-brother to Xiao Lon. As the son of the clan's leader, he is known as a "prince" and is the eldest of Ron's sons. Like his brothers, he left the village in his youth to train and perfect his art. After Ron's betrayal, his reputation with the remaining members declined as he was labeled "that traitor's son".

The King of Fighters 2003
Hoping to hunt down the clan's traitor, he partakes in several jobs as an assassin. As he does so, Ash Crimson mysteriously appears before him and makes his acquaintance. Through Ash, Duo Lon also meets Shen Woo. Liking their company enough to be friendly with them, he agrees to enter the 2003 tournament with them. Although they did not win, he disappears when he senses Ron's presence.

The King of Fighters XI
After discovering Ash's true objectives, he is invited to Elisabeth Blanctorche's mansion, along with Benimaru Nikaido. There, they discuss Ash's thievery of Chizuru's powers, the existence of Those From the Past, and their experiences during the 2003 tournament. The trio forms the Rival Team and track down Ash. They find him after he steals Iori's powers. Benimaru sees Shingo and Kyo's beaten states and threatens Ash for an explanation. Before either members can interrogate him further, Ash teleports away and warns that Kyo will be next.

The King of Fighters XIII
Although he is still dedicated in his mission to hunt Ron, he is curious about Ash's intentions and respectfully parts ways with Benimaru. He meets up with Shen Woo to try to discover anything regarding their former teammate's whereabouts. At a dead end with his search, he remembers that Elisabeth had some connection with Ash and they work together to find her.

After Ash erased himself and Saiki from history, all memories of him were erased from all who knew him, including Duo Lon. In their team's ending, both he and Shen Woo respectively give Elisabeth time to mourn over Ash's "death".