Sai is a Ghost Duelist in Yu-Gi-Oh! World Championship 2007.
She first appears in LP Survival. She is one of the twelve random duelists that the player encounter in LP Survival ∞ Mode. When the player encounter a !! sign at the bottom of the screen, the player could encounter her and face her in a Duel. By beating her, she will be unlocked as a Ghost Duelist.
In World Championship 2007, Sai uses a "Monarch" Deck titled "The Emperors".