Kira

Light Yagami, known as Kira, is the protagonist villain of the manga/anime series Death Note.

Nicknames
Not long after Light started killing criminals, websites around the world already called him of "Kira", which is japanese romaji to the english "killer". After the death of the detective L. Lawliet, Light assumed his role as L, the best detective of the world.

Death Note
The death note is a supernatural notebook which has the power to kill any human whose name is written into it. It is this premise which forms the central plotline in the Death Note series.

Shinigami normally use death notes to kill humans from the shinigami realm, thereby adding each human's remaining years of life to their own. Rogue Shinigami are gods of death who drop extra death notes from the shinigami realm down to the human world in order to allow humans the use of their spare killer notebooks. Historically, humans have either killed other humans with the death notes or ended up burning and therefore destroying the death note for a number of reasons.

The death note is regarded to by detective Nate River (Near/L) as the most deadly weapon ever used in the history of mankind.

One of the eyecatch rules of the shinigami realm states that only 6 death notes can exist in the human realm at any one time. However, it is unknown how many killer notebooks exist in the shinigami realm, as well as how they are made.

Shinigami
Shinigami (死神), or Gods of Death, are a race of extra-dimensional beings who survive by killing humans to extend their own lives. Shinigami in this series are not responsible for every death that occurs; people will eventually die regardless of whether or not the shinigami pay attention to them, but a shinigami can end their lives sooner than intended to extend their own lifespan.

Modus operandi
Light's m.o. was to murder criminals in the most variated ways by using his death note.

Divine Rule
Light believes that he is the only human that could have purged the world of evil, showing an extremely narcisist nature. He has the idea that he must have been destined to find the death note that Ryuk dropped in the beginning of the series. That is part of the reason that Light took it upon himself to become the "God of the New World" that he would create. With the death note, he could now perform divine justice by passing judgment on the wicked. He now had in his hands, the means, and in his heart, the will to do what no other human could do: kill every wicked and evil person on earth.

The rest of the world was definitely willing to follow Kira and even to worship him as their new god. To assume divine justice, you must have the support of the gods as well as the religion's followers. Light came close to gaining power over the planet, and would have been the first human to control all of earth. It is in this way that he would have been god for the rest of his life. Interestingly, producing an heir before death would have secured his power as Kira: L had groomed Mello and Near, and as such prepared both to become the true heir to L. Light most likely never thought of having children or successors, as he believed he was god and, therefore, could never die.

The Kira Case
In 2003, Detective L. Lawliet - under the alias of L - started working on a series of strange heart attacks, which were causing the death of several criminals and wicked people. L was the only one who could pinpoint the location of Kira as Kanto region in Japan, and, later, getting a list of suspects related to the japanese police. After some further investigation, Light Yagami became the main suspect of the Kira mass murders, but was able to avoid his and his accomplice, Misa Amane (the second Kira)'s execution by using the death note's fake rules written by the shinigami Ryuk. After that, Light and Misa lost their memories and started working along with L (Ryuzaki) to catch the third Kira, Kyosuke Higuchi. After Higuchi was captured, Light killed him, regaining his memories, and used the shinigami Rem - who ended up dead for writing L's name for the sake of keeping Misa Amane alive - to kill L.

For three years, Light Yagami - Kira -, Misa Amane - 2nd Kira - and Teru Mikami - X-Kira - executed the criminals of the world, and Kira became practically a religion. After that, the successor of L, Detective Nate River - Better known as Near - presented himself to the actual L, Light Yagami, as N. Near then created the Special Provision for Kira, or SPK, a group of first-class investigators to catch Kira. Shortly after Misa's replacement - Kiyomi Takada - became Kira's spokeswoman, the mafia boss Mihael Keehl (a.k.a. Mello) and his accomplice and best friend, Mail Jeevas (a.k.a. Matt) kidnapped her. Matt was killed by Takada's bodyguards and Mello by Kiyomi herself. Takada's name had already been writen in the death note by Kira, causing her to die in a massive explosion shortly after Mello, destroying all evidences against Light. After Near's investigation, he set a trap tusing two fake death notes, at the same time, Kira used Teru Mikami to try and kill all people who knew about the existence of the death note, but, as the note was a fake made by SPK, Mikami was captured - and later suicided - and Light was killed by the shinigami Ryuk. 2nd Kira died some years later, ending the existence of Kira until C-Kira appeared.

FRICK PLEASE ADD YOSHIKAGE KIRA