ES (Eternal Sabbath) is a gene developed by a group of scientists who sought immortality. The presence of the gene grants the carrier up to 200 years of life immune from all viruses. Though the scientists' original intention was to demonstrate the feasibility of eternal life, ES unexpectedly has the additional power of mind-control and memory-alteration.
A female neurology professor, Mine Kujo, meets a man by the name of Ryosuke Akiba and discovers that he is a genetically-engineered human with the ES gene. Together, they pursue a more dangerous ES-carrier who had escaped from the research center.
Mine Kujo: A neurological specialist from a physiology research institute from the U.S. Extremely intelligent, often scaring her "omiai" (speed-dating) partners away by speaking about the exact kind of thing you're not supposed to speak about when dating someone - the reason why alpha lions eat lion cubs, ray mantas' mysterious and exciting way of procreating, that sort of things. She isn't quite the regular woman you meet every day - though she could be called a beauty if you look closely, she is more the type of woman who's talking, when not screaming to herself. She is qualified by Shuro as a "dense woman", in that she is one of the very rare humans whose minds cannot be totally invaded and controlled by the powers of an ES; mindspeaking and (painful) hallucinations are as far as it goes.
Izaku: Shuro's clone, created to investigate why ES00 was the only one to survive, since Shuro was the original ES. Created 10 years after Shuro's birth, his code name is ES01. He grew in a mechanical womb during approximately five years. Any light or sound would be kept from reaching him in order to avoid the "rise of sentience"; the researchers planned on dissecting him to study his viscera right after taking him out of the mechanical womb. His name originates from the Old Testament; the devout Abraham offered his son Isaac as a sacrifice to God. Like his namesake, Izaku was born to be sacrificed.
Shinichiro Sakaki: Used to be an immunology researcher at National Hygienic Laboratory. Another person Akiba can't manipulate.
Iwamura Yuri: Friend of Izaku. Like Izaku, Yuri-chan has an infantile sense of right and wrong, and is complacent and encouraging in Izaku's killing. She is also a victim of child abuse at the hands of her mother.