Alex, known as Kohei Aoyama in the Japanese version, is a character from Yu-Gi-Oh! 5D's.
Kohei's family name, Aoyama, means "blue mountain" but can also mean "burial place". His given name means "I am".
In the English dub, he talks a lot, and he can even be heard saying "I love to talk" while Yusei is thinking during Episode 9.
He first appears at the Facility. After Yusei Fudo is transferred to the same room as him, he tells Yusei that he has been planning to escape and invites Yusei to come with him, but Yusei says he wants to escape with Tanner and Yanagi. In the Duel between Yusei and Mr. Armstrong, Alex fixed the system that Armstrong had rigged to prevent himself from getting shocked.