Guilt and remorse play a significant role in Light Yagami's character development in the anime "Death Note." Initially, Light's actions are driven by a sense of righteousness and a desire to create a better world by eliminating criminals. However, as he continues to use the Death Note, he starts to experience guilt and remorse for the lives he has taken. This inner conflict ultimately leads to a darker side of Light's character, as he becomes more consumed by power and loses sight of his initial motivations. The feelings of guilt and remorse contribute to the moral decline of Light Yagami and shape the overall narrative of the series.