Jae-ha

He is the descendant of the Green Dragon and possesses the power of a dragon in his right leg. His power allows him to jump high and long distances that almost make it look like he can fly. It also makes his leg incredibly strong and lethal when used to kick. He's a big flirt, he doesn't care whether it's a man or a girl.

[Spoiler] Twenty-five years ago, Jae-ha was born in the Village of Ryokuryuu and Garou, the previous Ryokuryuu, took care of him. During his childhood, he was confined in chains within his room to prevent him from escaping the village and also from repeating the tragedy that happened eighty-five years ago. On his every attempt to flee, he was always stopped by Garou and he was beat up as punishment. [/Spoiler]

(Source: Akatsuki no Yona Wikia)