Light Yagami in the anime "Death Note" initially believes he is justified in using the Death Note to rid the world of criminals and create a utopia. However, as he continues to use the Death Note, he becomes more morally compromised and faces internal conflicts about the rightness of his actions. Ultimately, Light's desire for power and control overtakes his initial intentions, leading to a moral downfall as he becomes more ruthless and manipulative in his quest for justice.