Death Note's Creator Had One Rule That The Series Could Never Break
This post contains spoilers for "Death Note."
"There is no Heaven or Hell. No matter what you do while you're alive, everybody goes to the same place once you die. Death is equal."
Fans of the original "Death Note" anime will remember these words spoken by L, who acts as the antithesis to Light Yagami throughout most of the series. However, in the "Death Note" manga created by Tsugumi Ohba (alongside artist Takeshi Obata), these words are spoken by Ryuk, the Shinigami who dropped the titular book on Earth for his own amusement. Interestingly, Ryuk tells this to Light, who is about to die within 45 seconds after Ryuk writes his name in the Death Note.
While the entirety of Ohba's "Death Note" is rife with twists and turns, with Light usually emerging victorious, this particular moment marks the end of Light Yagami and his rule as the self-proclaimed "god of the new world." Gone is the cold, composed villainy of the character, as Light finds himself at the end of the line, desperate to survive the ordeal. However, it is too late: Near, L's successor, wins, and Light dies, knowing that his actions were in vain. This is how Ohba always intended for the manga to end, and he managed to retain this narrative decision in the end.
However, apart from the narrative certainty of Light dying at the Yellow Box warehouse, there was one particular rule that Ohba had when it came to "Death Note." This particular rule reinforces a recurring theme in the manga: the blurred lines between right and wrong, between what's righteous and what's evil.
No heaven, no hell
In a rare interview with Ohba, whose real identity remains unknown, the manga-ka said ending the manga with Light dying was always part of the plan. Apart from this, the most important part of "Death Note" that he did not want to change on any account was the notion of "nothingness" after death in the story. Ohba said:
"One thing that I didn't allow to be changed was the notion that 'when you die, you become nothingness.' Luckily, I was able to keep this part, and the series turned out almost exactly as I had originally planned...For me, one of the premises of the series was that once a person died, they could never come back to life. I really wanted to set a rule that bringing characters back to life is cheating. That's why death equals 'nothingness.'"
This notion is expressed in the scene where Ryuk talks about death being equal, hinting that Light would not be going to heaven or hell, as they do not exist. Instead, he must go where everyone does after death: pure nothingness, from which there is no return. Within the mythos of "Death Note," a person's deeds while they're alive do not dictate the quality of life after death, as there is no life after death. Instead, justice is achieved in the realm of the living, as seen with the triumph of Near and the SPK (Special Provision for Kira) in the end. Even on the verge of death, Light puts up a childish fight, refusing to either die or go to prison, but his fate was sealed the moment he picked up Ryuk's Death Note. Unlike the anime, where Light quietly surrenders to death, the manga shows Light in a pitiable light, unworthy of anyone's mercy or pity.
Death, the great equalizer
The reason why Light/Kira's death in the manga is more resonant than in the anime is that it usurps the core intentions behind his actions. Light starts using the Death Note with seemingly good intentions; the dude simply wants to eradicate crime by killing off criminals. However, there's little nuance to this motive, as Light starts killing indiscriminately and develops a god complex in the process. His version of "justice" is fueled by narcissism and a twisted need to play judge, jury, and executioner, while believing that he is exempted from the same yardstick.
Despite Light's shrewd, charming villainy and his penchant for undercutting everyone's plans to capture him, he fails miserably in the end. Ryuk, the shinigami who is bound to him through the diary, becomes the reason for his undoing. Interestingly, Ryuk does not act out of a need to dole out justice—the shinigami's boredom has been satiated, and he simply wishes to return to his realm. In order for that to happen, Light needs to die. So he does.
Light wanted to leave behind an unforgettable legacy. He does succeed to an extent, as the citizens of Tokyo perceived Kira to be a just, god-like figure for the longest time. However, Light's sudden death in the warehouse directly undercuts what he wanted to achieve. By the end, Near and the SPK are aware of Light's true identity; he is outsmarted in his own twisted game, and has his death scheduled in the diary that used to be his weapon. Death is the great equalizer, reminding Light that he will be going to a place where every dead person went, including L and the people he murdered. Light Yagami isn't special, and his legacy is a broken one: one that isn't worth remembering.