Luffy's most dominant traits are his apparent lack of common sense, utter fearlessness, and unwavering belief in himself. He generally marches at the beat of his own drum, unwilling to approach anything in a delicate or nuanced matter. That said, Luffy has a penchant for being able to see through the heart of the case, often able to accurately call out someone's personal flaws. He's stupid but good at reading people.