Why ( どうして / doushite ) is the one-hundred-fifth chapter of the Elfen Lied manga series.
The first Saseba operative mounts the steps to the ravaged remains of the lighthouse tower, relishing this last confrontation with Lucy. Kouta tells Yuka to take the others and go, and despite Lucy/Nyu's pleas for his safety, he vows to stay with her until the end, since she risked her life for his, and the threat of death in that light doesn't scare him. Nana whispers to Mayu that she can kill all the soldiers surrounding them, but Mayu urges restraint, not wanting to lose their home, and urging her to leave it all up to him.
The operative demands revenge for the thousands of people that Lucy has slaughtered, and threatens to kill Kouta for interfering. Lucy/Nyu urges him to leave, since in fact she has killed those thousands, and his death would render her sacrifice pointless. Thanking her friends and loved ones for the good times she had and saying that leaving them is painful, the essence leaves her horribly mangled body, prompting Nana to warn Kouta that the presence now inhabiting the body is neither Lucy nor Nyu. It is the DNA inner voice, in actual control for only the second time, and in agony from the nearly useless melted form, stating it does not wish to die, for which the Operative chastises it. Nana pulls Kouta away from the soldiers just in time as the Voice unleashes its vectors to tear through the soldiers one and all. The vector power rises again, with the enraged inner voice determined to destroy the world rather than hand it over to the humans it hates before her body melts.
Buildings begin to shatter, and the vectors have now become visible from orbit as they violently rampage throughout the entire country. Kouta's urgings for it to stop only direct its wrath back at him, who the voice blames for all its troubles. The spirits of Lucy and Nyu appear and shield him. They explain that they are only the illusions of their consciousnesses within their DNA, something only he can see, and that they can only protect that one spot, not the whole world, from the voice's rampage. They then remind him of the childhood promise he made, should she ever start killing lots of people.