Ash has the personality, charisma, and skill to gather large groups of individuals together under his influence. Not only is he excellent in combat and an incredible marksman, but he's also highly intelligent with an IQ of 200. His intelligence lends itself well to solving the mystery of 'Banana Fish' and he has also been stated to be quite well-read, knowing his way around the newspaper's daily columns and political novels - unusual for someone who did not finish middle school.
Along with his remarkable intelligence, Ash's good looks and charisma allow him to sway the will of people to his benefit in dire situations, and he's well aware of it. Despite the influence he holds over others, however, Ash is mistrustful and holds most people at arms-length except for a few select friends in his inner circle, the most notable being Eiji Okumura. He is not afraid of death not because of courage, as he calls himself a coward, but because of his disillusionment with his own life.
(Source: Banana Fish Wiki)
