|Name in Japanese||ウォン・カーイ|
|Romaji Translation||Won Kāi|
|Debut (Anime)||Gosick Episode 13|
|Debut (Light Novel)||Volume IV|
|Appears in||Anime, Light Novels|
|Voice Actor (Japanese)||Eirou Ishikawa|
Kai Wong is a professional magician and a colleague and friend of Brian Roscoe. His interest in finding out the mystery of the alchemist Leviathan has brought him to the clock tower inside Saint Marguerite Academy, where he is later found dead, adding to the list of unexplained deaths in the clock tower. After Victorique de Blois's deduction, it is revealed that Kai Wong died of poison from the rose trap.