Light Yagami

"This world is rotten, and those who are making it rot deserve to die. Even if it means sacrificing my own mind and soul, it’s worth it. Because the world… can’t go on like this. I wonder… what if someone else had picked up this notebook? Is there anyone out there other than me who’d be willing to eliminate the vermin from the world? If I don’t do it, then who will? That’s just it: there’s no one. But I can do it. In fact, I’m the only one who can. I’ll do it. Using the Death Note, I’ll change the world."

- Light Yagami. "If we catch Kira, he is evil. If he rules the world, he is justice."

- Light Yagami to the Task Force. "I’m a hardworking honors student who’s considered to be one of Japan’s best and brightest. And I… I will become the God of this new world."

- Light Yagami expressing his own goal.

Light Yagami is the main protagonist of the Death Note manga/anime series as well as its multiple adaptations.

Light was a Japanese high school senior who found a notebook called a Death Note. Anyone whose name is written in the notebook will die. At first skeptical of its power, Light tested its power on two criminals. After realizing the power of the notebook, Light went mad with power, deciding to use the notebook to rid the world of criminals and create a new world full of law abiding people he accepts. Light would then make himself the God of this new world.

The series charts his use of the notebook and his struggles with the Japanese police, the detectives L, Mello, and Near, as well as his associations with other notebook users, such as Misa Amane and Teru Mikami. His online followers dubbed him "Kira" in Japanese, based on the word "killer" in English.

Old Personality
Light did not start as a murderous vigilante at the very beginning of Death Note. He was a sympathetic and popular student who was bored of his life, with real concerns about fixing the world of its various injustices. He regained his old personality upon giving up ownership of the Death Note. However, even then, he agreed with the principles of "Kira".

It is upon discovering the Death Note and seeing its deadly effects, that Light, believing himself to be the "chosen one" who would save mankind from destruction and evil (even if Ryuk explicitly stated multiple times during the story that he randomly dropped the book somewhere in the world), went mad with its power.

Current Personality
"My dad? Ha.. you mean Soichiro Yagami... That's right, Matsuda. In this world, all those ernest people like him fight for justice! They always lose! You want a world where people like that are made to be fools?! I know you understand, so kill the others! Shoot them!"

- Light Yagami trying to convince Matsuda to kill the others. Light is an unfeeling sociopath who is only driven by his immense hatred of criminals and is ready to do anything in order to become nothing less a living deity. Self-centered, he created the identity of Kira in order to lead a cult devoted to himself, even though his followers were unaware of him being their savior. He even planned to kill unhealthy or lazy people once he became a God in order to build a strong, disciplined utopian society based on an eugenist ideology, though he did not hold supremacist views.

He is an extremely clever, psychopathic and sly master manipulator, who can easily act as an innocent and friendly individual in public who would never kill someone, while secretly killing dozens or hundreds of people each night. He was able to convince Misa that he cared about her and that he was grateful for everything she'd done for him, when he only thought of her as a pawn which he'd kill once she outlived her usefulness. He was also able to fool Takada, a much more clever woman, into being his “queen” and thinking that he loved her, when it turns out, like Misa, he only thought of her as a pawn, as seen he killed her without hesitation when the opportunity arose to kill Mello and to prevent her from revealing any secrets about Kira. A criminal mastermind, he often elaborated unbelievably complicated schemes to compensate his lack of henchmen, involving pretty much nearly everyone around him.

He is also shown to be a sadist; though he is not explicitly aroused by the act of giving death, he is sometimes shown smiling devilishly, hinting his vicious tendencies. Such an instance is seen when he kills Naomi: after she prepares to commit suicide, Light mockingly tells her that his father's cellphone is available while smiling, solely doing this for pleasure. He also could barely contain his laughter during his final confrontation with Near when he thought that everyone in the room would die, demonstrating the sadistic pleasure he took in their deaths and his would-be victory.

He is also shown to be delusional in his quest, believing himself to be doing everything in the name of justice and justifying all of the deaths of criminals, police, even his closest allies such as Takada, as necessary to complete his goals and change the “rotten” world. When Ryuk claims that even after all the world's criminals are dead, Light would be the last criminal left, to which the teenager rebuked and viewed as ridiculous.

As he continued his crusade as Kira, he became an ungrateful, hypocritical and self-centered dictator, viewing people, his fanatical followers, his devoted henchmen, friends, relatives, his father or even his lover and second Kira Misa Amane who saved his life multiple times (although she almost ruined his plan due to her stupidity) as mere tools in his quest of godhood.

He doesn't express fear while speaking with Ryuk or others Shinigamis, despite their mysterious and murderous nature, as well as their immense magical powers. Light does fear instead L Lawliet, the enigmatic and genius detective from the Task Force - and the only character in Death Note who's at least as intelligent and sly as Light. Upon their first encounter, L was at first glance suspicious of Light being Kira, but soon befriended the latter (even though he kept strong suspicions about Light's “secret hobby”). Light would use this to gain the upper hand through his most extraordinary scheme involving Misa Amane, thus eventually killing him with no second thought; he went so far that he even shout on his tomb that he “won” and nothing would stop him now.

He temporarily regained his old personality when he turned amnesiac; though this did not last long, as upon recovering the Death Note as well as his memories, Light turned into an even more sadistic and manipulative Machiavelli.

Despite his heightened intelligence and calculating nature, Light's arrogance and overconfidence are his greatest weaknesses. It was seen in his final confrontation with Near, where he boastfully claimed he won before everyone was supposed to die, which only further proved his identity as Kira. Claiming to be a living divinity, Light, murdered by Ryuk, showed that he was nothing more than a loathsome serial killer at the very end, and not the god he thought he had become.

Underneath his calm, collected and intelligent demeanor also lies the heart of a coward: upon being revealed as Kira by Near, he rushes in fear upon trying to be handcuffed, and when he tries to kill everyone in the room with a piece of the Death Note, he frantically tries to get Matsuda to kill the others, even though Light was prepared to kill him just moments before. After he was shot, he flailed like a worm on the floor, and in a futile attempt told Mikami to write down the names of the detectives, even though Mikami didn't have the Death Note, and desperately calls out for Misa and Takada, even though both are not there.

Light's last act of cowardliness until his death differs between the manga and anime, in the manga, Light remorselessly sends other people to their death. However, when his own death comes as Ryuk writes Light's name using the same method he uses to kill others, he gets terrified and screams that he doesn't want to die. He even tells Ryuk to reverse the process even though he knows full well that it cannot be reversed. He then died pathetically screaming and crying. In the anime, he flees when Mikami distracts everyone in the room and shows some semblance of regret for his actions, having envisioned a life he could have lived if he haven't found the Death Note in the first place. Rather than fearing for his death, He silently succumbed to his own fate when Ryuk writes Light's name and as he alone slowly pass away, he sees a figure of L looming over him.

Trivia

 * Light's last name "Yagami" is also the last name of Hikari in the Japanese version of Digimon, whose crest is the Crest of Light. Also, his nickname "Kira" is an anagram of "Kari", which is Hikari's English name.
 * In a pair of four-panel omake chapters in the manga, Light is shown to soften his heart around Christmas time, even dressing as Santa Claus and giving out presents. However, his generosity only goes so far, as he will not get Ryuk the Gameboy Advance SP he wants because it is too expensive and Shinigami do not celebrate Christmas.
 * Both his actors Tatsuya Fujiwara and Masataka Kubota have stared in Rurnoi Kenshin movies where Fujiwara played Shishio Makoto and Kubota as ill-fated Akira Kiyosato.
 * Light's relationship with L is similar to Judas' relationship with Jesus. The scene where L massages Light's feet highlights this as it was a reference to Jesus washing Judas's feet, aware of his betrayal and that his demise was coming soon.

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Light Yagami