The young man was created in a lab, given a gene called ES - Eternal Sabbath. As a result, he will live to be two hundred years old. He has the power to enter your mind and make you think you've known him your whole life - or forget him, however he wills. He is known as Shuro, though he has taken other names as he needs. Today, he is Ryousuke Akiba.
A series of events brings Shuro to the attention of a brain researcher named Dr. Mine Kujou. She is resistant to his powers, which arouses his interest. However, at the same time, she encounters another resistant - Sakaki, a researcher from the laboratory that created Shuro... the last survivor, as it so happens.
For the lab that created Shuro also created a clone, Izaku. The intention was to dissect Izaku in order to study what exactly makes an ES tick. But when Izaku discovered this plan, he rebelled and killed everyone in the lab whom he could before escaping.
Izaku's still out there. He has no empathy for any human being. If he is not stopped, the consequences could be nightmarish. And Shuro is the only one who can truly stop him.
Now how will they convince Shuro of that?
Eternal Sabbath is an eight-volume manga by Fuyumi Soryo, who previously did MARS.
This manga contains examples of:
- Abusive Parents: Yuri's mother beats her the same way her father beat her.
- Accomplice by Inaction: Yuri's mother was herself horrifically abused by her violent father as a child. However she eventually admits that, while she hated and feared her father, she hated her mother just as much, if not more, for being too cowardly to try and protect her beyond meekly asking him to stop. Whenever her father beat her, her mother would buy her candy to try and apologise to her, but she could never even taste it.
- Anyone Can Die: Out of the named characters, Mine, Sakaki and Mrs. Akiba are the only survivors at the end.
- Berserk Button: Abortion reminds Izaku far too much of his original fate.
- Cloning Blues: Izaku was created for the sole purpose of being killed and studied.
- Creating Life Is Bad: Exemplified by Izaku, considering what he does after his creation.
- Death of a Child: Izaku kills a lot of kids over the course of the series. Even Yuri.
- Designer Babies: While it's never clear exactly to what degree Shuro was artificially created, both he and Izaku were genetically altered to implant the Eternal Sabbath gene.
- Enfante Terrible: Izaku, a five-year old super human who kills people because they bother him.
- Evil Counterpart: Izaku and Shuro share the same genetic code (the former being a clone of the latter), but while Shuro is able to learn to love, Izaku is spoiled rotten by his adoptive mother and becomes a murderous psychopath.
- Freaky Friday Sabotage: In the climax, Izaku attempts to steal the body of protagonist Shuro, and in the process psycho-kinetically lights his body on fire in an attempt to kill Shuro. While it looks like it's just a side-effect of the mind swap, his comments afterwards imply it is this trope.
- Freudian Excuse: Even the other characters admit Izaku has a good reason to be like he is. Being born to be a sacrifice does not do wonders for the psyche.
- Good Girls Avoid Abortion: Averted with Yuri's mother. When she finds out she's pregnant again as she's starting to rebuild a relationship with her daughter, she opts to terminate the pregnancy out of fear that she won't love Yuri as much as the child. Izaku kills her before she does, her death being played for tragedy and killing her is what seals Izaku's fate.
- Grand Theft Me: Izaku does this to Shuro... but doesn't realize that Shuro jumped out of Izaku's body before it was destroyed.
- Meaningful Name: Acknowledged in-universe: Izaku ("Isaac") was created as a sacrifice.
- Morality Pet: Yuri appears to have some sort of influence over Izaku, and he wouldn't kill anyone she doesn't want him to. However, this is subverted when Yuri starts to defy Izaku, and he promptly kills her without a second thought.
- Pet the Dog: Mine adopts a one-eyed dog at one point to save him from being put to sleep. Later, after sleeping with her, Shuro befriends the dog as well... without using his powers.
- Psychic-Assisted Suicide: Izaku likes to trigger these in the people who irritate him. Shuro has to do this once or twice, as well.
- Psychic Powers: Shuro and Izaku can both manipulate memories, read thoughts and emotions, and plant hypnotic suggestions.
- Someone to Remember Him By: The last page of the manga shows Mine learning she's pregnant with the late Shuro's child. There is the slight possibility that Shuro's mind is in the fetus.
- Spell My Name with an "S": The official English release translates Izaku as "Isaac".
- Taking You with Me:Dying from an autoimmune disorder that's given him progeria, Izaku decides to destroy as much of the city as he can in his "death throes".
- Younger Than They Look: Shuro's only fifteen or so. Izaku is around five. Both look twice their age.