Light Yagami (夜神 月, Yagami Raito^?), also known as Kira (キラ^?) is a fictional character and the main protagonist of the manga and anime series Death Note. He is an extremely intelligent, athletic, popular, but bored young man who finds the Death Note dropped by the Shinigami Ryuk by sheer chance. In the Japanese version of the anime he is voiced by Mamoru Miyano, and in the English version by Brad Swaile.

Tsugumi Ohba, the story writer of Death Note, said that his editor suggested the family name "Yagami" for Light. Ohba said that he did not feel "too concerned" about the meaning of the name (the kanji are "night" and "god"); he said that after he created the final scene in the manga he "liked" that the final scene created "deeper significance" in the name, of Kira worshippers worshipping him at night under the light of the moon.

Takeshi Obata, the artist of Death Note, said that he had "no trouble" designing Light as the character description presented to him, "A brilliant honors student who's a little out there," was "clear and detailed." As the weekly serialization continued, Obata simplified the design by subconsciously removing "unnecessary" lines and felt that he became "better" at drawing Light. When Chapter 35 appeared and the editor informed Obata that Light lost his memories, Obata had to draw Light in a similar manner as he appeared in Chapter 1; Obata said "It was like I had to forget everything I had learned." Obata said that he used "a lot of effort" to design Light's wardrobe. According to Obata, he encountered difficulty imagining the clothing of "a brilliant person," so he looked through fashion magazines. Obata envisioned Light as a "smart and formal guy" who wears formal shirts. Most of Light's clothing in Death Note is "fitted" and Obata avoided jeans.

Mamoru Miyano (宮野 真守, Miyano Mamoru^?, born June 8, 1983) is a Japanese voice actor, actor, and singer from Saitama Prefecture. He is best known for his roles on Ouran High School Host Club, Death Note, Mobile Suit Gundam 00, Kōtetsu Sangokushi and Steins;Gate. At the 2007 Seiyu Awards he was nominated for two awards for his role as Light Yagami in Death Note, and in 2008, he won the "Best Voice Actor" award at the 2008 Tokyo International Anime Fair. At the 2008 Seiyu Awards, Miyano won "Best Lead Actor Award" for his role as Setsuna F Seiei in Mobile Suit Gundam 00, and as Hakugen Rikuson in Kōtetsu Sangokushi.

Miyano began his career as a musician in 2007. He released his debut single, "Kuon" (久遠^?, lit. Eternity), in May on the King Records label. In March 2009, his debut album Break was released. Miyano married in late 2008. He and his wife have a son together.

Miyano started his voice acting career in 2002, providing the voice of Riku in the Japanese version of the PlayStation 2 video game Kingdom Hearts. He then voiced Kiba, the main character of anime series Wolf's Rain. He returned as the voice for Riku in the 2004 Game Boy Advance game Kingdom Hearts: Chain of Memories, and in Kingdom Hearts II in 2005, and in Kingdom Hearts Re:Chain of Memories in 2007.