Light Yagami, the main character in the anime "Death Note," initially believes he is justified in using the Death Note to eliminate criminals and create a more just world. He rationalizes his actions by convincing himself that he is purging society of evil and making the world a better place. However, as the series progresses, Light becomes increasingly consumed by his power and ego, leading him to justify more questionable actions and ultimately blurring the line between right and wrong. Despite his initial intentions, Light's sense of morality becomes warped as he becomes more entangled in his role as Kira.