Light Yagami

Light Yagami (夜神 月, Yagami Raito) is the protagonist and anti-hero of the story. At the start of the series, he discovers the Death Note and uses it to kill criminals, becoming known to the people of Japan as Kira (based on the Japanese pronunciation of the English word "killer"). He is characterized as an extremely intelligent, but bored young man, who is frustrated by the lack of justice in the world. He is confident of his own intelligence and how smart he is in relation to others.

His life undergoes a drastic change in the year 2003, when he discovers a mysterious notebook, known as the "Death Note", lying on the ground. The Death Note's instructions claim that if a human's name is written within it, that person shall die. Light is initially skeptical of the notebook's authenticity, but after experimenting with it, Light realizes that the Death Note is real. After meeting with the previous owner of the Death Note, a shinigami named Ryuk, Light seeks to become "the God of the new world" by passing his judgment on those he deems to be evil or who get in his way. Being a genius, Light feels that only he is fit to judge humanity and steer it on a proper moral course, viewing himself as the "god" of the new world he is creating.

A short time later, Light sets to work ridding the world of criminals, attracting the attention of the master detective L. Light and L encounter each other in a series of battles of wit throughout the first part of the series, though once the second Kira, Misa Amane emerges, L is able to corner them both. After giving up the Death Note briefly to clear their names, he is able to finally have L killed by manipulating Rem into saving Misa's life. With L dead, Light takes up his mantle to keep the world in the dark about L's death, becoming the second L while putting him in the perfect position to continue killing criminals. He comes into conflict with L's true successors, Near and Mello, during this time. After making a mistake in using Teru Mikami as a proxy, Near is finally able to corner Light. Having decided that it's time to end his game, Ryuk kills Light.

Education and Everyday Life
During the beginning of the series, Light is a third year high school student (12th Grade) at Daikoku Private Academy who also attends supplemental classes at Gamou Prep Academy. Light has a father, Soichiro Yagami, who is a member of the investigation team opposing Kira. In addition, Light has a mother, Sachiko Yagami, and a younger sister, Sayu Yagami.

In Spring 2004 Light becomes a first-year student (freshman) at To-Oh University, becoming one of two freshman representatives; L is the other freshman representative. During a tennis game with L at To-Oh, spectators reveal that Light was the junior high school tennis champion in 1999 and 2000; After his 2000 victory, Light quit tennis as he entered high school.

Fate
In the manga version, after completely losing his head and characteristic cool over the prospect of being arrested, and in complete desperation after his attempts to write Near's name down are thwarted by Touta Matsuda, Light begs Ryuk to help him. Ryuk reminds Light that he is on neither side, and fulfills his earlier promise to write Light's name in his Death Note, thus ending Light's life.

In the anime version, Light manages to flee the warehouse after Mikami commits suicide. Near instructs the team that there is no reason to pursue Light given that there should be no more hidden Death Notes, and Light's wounds would prevent him from getting far. Despite this, Shuichi Aizawa, Kanzo Mogi, Hideki Ide and Matsuda follow Light but are unable to find him before he dies on the staircase of a nearby warehouse due to cardiac arrest from Ryuk writing his name in his Death Note. As Light slowly closes his eyes, an apparition of L appears before Light, mirroring Light standing over L in episode 25 at L's death. At the end of the Director's Cut the last line Ryuk says is, "Isn't that right, Light?" This line does not imply that Light has become a Shinigami after death, because a Death Note rule consistent to both the anime and the manga states that all humans go to MU (become Nothingness) when they die. Even so, some people believe that light became a shingami, and the directors cut was Light and Ryuk talking about their adventures in the human world.

Film Summary
In the film, a few changes were made to Light. At the film's beginning, Light is a first-year university student studying Law, instead of still being a high school genius, as in the beginning of the manga and anime. Light's motives differ; his boredom trait does not exist, and he instead uses the Death Note out of frustration from the perceived failures of the Japanese justice system. Light, prior to his discovery of the Death Note, hacks into the government database and finds that the government secretly acknowledges that many criminals are unable to be prosecuted. Light discovers the Death Note in an alley during a rainy night after encountering Shibuimaru in a club and throwing a law book into the rain in a rage. Light meets Ryuk after killing Shibuimaru. Light has a girlfriend, Shiori Akino, who attends his university. Light kills Shiori at the end of the first movie to gain sympathy from L.

After Rem "kills" L and kills Watari, Light writes his father's name in an attempt to kill him, an attempt that ultimately fails. The endings of both the second movie and the manga are similar. In the second film, after being exposed as Kira, Light asks Ryuk to write the names of the team members in the book during the climax. The police shoot but do not kill Ryuk as he writes in the Death Note. Light laughs until Ryuk shows Light the Death Note, revealing that Light's name was written in the book. Light tries to stop Ryuk, passing through the shinigami. Light dies in his father's arms, begging him to believe that he acted as Kira to put justice, which Soichiro had taught him since his childhood, into practice.