Deception and manipulation play a significant role in Light Yagami's relationships in the anime "Death Note." Throughout the series, Light uses these tactics to manipulate others to achieve his goal of creating a new world order where he reigns as a god-like figure. He deceives his allies, such as Misa Amane and Teru Mikami, as well as his adversaries, like L and Near, in order to stay one step ahead and maintain control over the situation. Light's relationships are often built on lies and manipulation, ultimately leading to a tragic downfall as his true nature is revealed.