Shun Kakei

Kakei is serious, disciplined and intensely competitive. His experience in America initially damages his confidence because the size of American players makes his own abilities seem inadequate.

Seeing another Japanese player excel changes his outlook. Kakei becomes determined to improve rather than accepting physical disadvantage as a reason to quit, and that experience remains a major source of motivation after he returns to Japan.

He also has a strong sense of responsibility toward Poseidon. Although not its formal senior captain, his ability and seriousness make him a natural on-field leader among the team's younger players.

Kakei combines unusual height with long arms, speed and strong defensive instincts. His reach allows him to make contact with runners from distances at which shorter linebackers cannot, reducing the effectiveness of evasive cuts.

He can use leverage to control smaller opponents with one arm and is intelligent enough to analyze offensive systems rather than relying purely on physical measurements. His ability to identify weaknesses in Deimon's formations makes him particularly dangerous against Sena.

His long reach provides a natural answer to runners who depend on sudden lateral movement. Even when a runner changes direction, Kakei can cover additional space without completely repositioning his body.

Kakei attends school in the United States during middle school and becomes discouraged by the physical superiority of many American players. He considers giving up football until witnessing a Japanese player wearing an eyeshield compete successfully at Notre Dame.

Inspired, Kakei trains and eventually challenges that player, promising that they will meet again. When he later encounters Deimon's Eyeshield 21 in Japan, he immediately doubts that Sena is the same person.

Kakei's testimony becomes an important clue that Hiruma's invented Notre Dame story accidentally overlaps with the existence of another player who genuinely used the Eyeshield 21 name in America. The identity behind that encounter becomes important much later in Sena's career.

Sena Kobayakawa initially disappoints Kakei because he does not match the player Kakei remembers from America. Their game nevertheless forces Kakei to judge Sena Kobayakawa on his own ability.

Kengo Mizumachi is Kakei's fellow Poseidon player and one of the team's other major physical threats.

Osamu Kobanzame is Poseidon's captain, while Kakei provides much of the team's on-field defensive leadership.

The player Kakei met in America later re-enters his story as the opponent he had spent years hoping to face again.