The World's Most Sad Story of Children and a Dog refers to the story of two children who lived as soldiers of the Russian government, detailing how they and a dog under their care all met their deaths one night. The story's propagation by Elena's hand lead directly to the creation of Kagamine Rin, Len, and Camui Gackpo.
At some point in the twentieth century, multiple young orphan living in Russia were taken in by the government and brought up as child soldiers, desensitized to killing for their country and given drugs to cope with their duties. These soldiers were largely identified by wearing yellow scarves. Among them, a young girl named Irina was also brought up as a child soldier and developed a relationship with another boy in the group, who wore a yellow and red scarf. During this time, all the children were indoctrinated to idolize Vladimir Putin.Meanwhile, the suffering Irina one day took in a small dog and became fast friends with her animal companion; as a result, she stopped taking her drugs. At some point she was called out for her work and left the dog in the hands of her male comrade, and the boy chained the animal up as a result. Some time later, the dog began to miss his master and broke through his chains, escaping from the other children and stealing the yellow scarf from the boy. Now free, the dog fled into the snow to find Irina while he was pursued by Irina's male comrade and all the other drug-addled children.
Returning home that night, Irina encountered her dog in the snowstorm just as all of her comrades caught up to the animal and urged the boy to shoot it, the boy laughing as he pulled the trigger. Driven into a homicidal rage at the death of her dog, Irina murdered all of her comrades then and there with a machine gun. Afterwards the child shot herself in the temple, putting an end to her service.
- "It's being distributed all over the world, the beloved "the world's most sad story of children and a dog""
Hoping to quell the scandal, Putin ordered an assassin named Urusei Teppannov to insert a virus into the data files and discredit the story, claiming that it was a hoax. He then ordered him to assassinate Elena to keep her quiet about the truth. The data files, all except Irina getting away from their viruses, all entered at some point the Vocaloids Camui Gackpo, Kagamine Len, and Kagamine Rin. The latter two having their memories removed later on, they lived relatively obscurely in Tokyo with the story they carried forgotten.
At some point, Kagamine Len reuploaded his part of the story by accident and remembered his "past life" as the dog. As a consequence, he later reuploaded Kagamine Rin's part of the story into her so she would remember her "past life" as Irina. A long time later Rin was destroyed in her data interior, taking her side of the story with her, and Len remained behind with his memories intact.
As the story spread over the internet, many civilians were shocked by the revelations contained within; due to the tragedy of the story, it quickly became loved among the populace and wildly retold; it was because of this popularity that the masses were conversely disappointed to learn that it was allegedly a hoax.
As a result of the information the common people, as well, began to seriously question Putin's regime and the civil rights violations carried out by the government. Due to this, the Russian government also became concerned about the propagation of the story, with Vladimir Putin taking efforts to discredit the tale and blame it on America.
Because of their own involvement in the story as the data files, Kagamine Rin, Len, and Camui Gackpo were all dragged into the political struggle involved in its propagation. As a result, Camui was sent to destroy Rin and Rin, afterwards, allowed herself to disappear after remembering the entire truth. Hatsune Miku, as well, did research into the story and was able to convey the majority of the events to Kagamine Len.