Jack Chu

Race: Human
Hair: Purple
Eye Color: Black

Mantle is a character who recognizes the birthmark on Kaiba's stomach. He chases Kaiba and Hyo-hyo hoping to capture and sell his body.

The symbol on Kaiba's stomach is the symbol of Warp, the king of memories.

Mantle has purple hair that he wears in a mullet. He wears a signature purple cape.

(Source: Kaiba Wiki, edited)