Kiryuu Kyousuke

Japanese name:	鬼柳京介
Nickname:	Kalin Kessler

Kiryu Kousuke (Kalin Kessler in NA localisation) was once the leader of a group called The Enforcers ("Team Satisfaction" in the original dub) with Yusei, Jack and Crow. The group would go around battling rival duel gangs. As time went on however, he became a bit more sadistic against his opponents and started going out of control and hurting his opponents as a result, which caused Crow, Jack and Yusei to leave. Kalin decides to provoke Security and attacks a Security officer. When Yusei tries to take the blame for it, his attempt fails and Kalin is arrested. Misunderstanding the situation and believing Yusei had sold him out, he later becomes a Dark Signer, branded with the Giant birthmark, in order to get his revenge on Yusei. Their first duel is canceled due to a malfunction on Yusei's Duel Runner, but he loses his second duel with Yusei, when Yusei's feelings allows him to synchro summon Majestic Star Dragon. He forgives Yusei before disappearing.

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