Leona Heidern is a character introduced in The King of Fighters '96 as the new member to the Ikari Team. Before production for her debut game began, developers wanted to create a suitable replacement for Heidern as a part of the game's overhaul. Leona was conceived to be an Orochi descendant by the time of her debut and her designers took special care to let their interests at the time reflect in her actions.

The four episodes are set in Southtown, the imaginary city well known to all fans as the stage of numerous death matches throughout the KOF series. Many past heroes of the saga make their appearance here, and the four plots intertwine to create a large-scale drama, that is also linked to the story of KOF Maximum Impact 2. 

2003 Tooniverse Voice actor in Korea Rhee Yong Sin (Hangul:이용신) is a Korean voice actor.  She joined the On-Media Voice Acting Division's voice acting division in 2003.  

(Source: Wikipedia)

King of Fighters is a battle between the strongest teams of 3 in the world. The story revolves around Kyo Kusanagi one of Japan's team when they reach the end of the King of Fighters '95 tournament and what follows after they get back to Japan.
 
Note: It's based on the 2D fighting game series King of Fighters.

Teams of fighters from around the world have gathered to answer one burning question: Who's the strongest warrior alive? Every single character from the legendary The King of Fighters video game series is on wild display in this brand new, high-octane fighting manga! 
(Source: Seven Seas Entertainment)

World-renown animator Masami Oobari directs a special KOF XV animated short using his unique and iconic style. Check out your favorite KOF XV characters kicking butt in this awesome animated video!
 
(Source: YouTube video description, edited)