World Embryo (ワールドエンブリオ Waarudoenburio) is a Japanese manga series by Daisuke Moriyama. It has been serialized by Shōnen Gahosha in Young King OURs since 2005 and collected in four bound volumes as of August 2008. The story follows a group of humans who combat monstrous creatures that spread around by using cell-phone signals. The series is licensed for an English language release in North America by 2009 from Dark Horse Comics, in Australia by Madman Entertainment, in Singapore by Chuang Yi, and in Russia by Comics Factory.
At the start of the series, high-schooler Riku Amami receives a cellphone picture from his dead sister Amane with a hospital in the background. When he visits the said building, he is attacked by electromagnetic monsters called Kanshus, which travel and reproduce using cellphone signals: if a human hears his cellphone giving off an eerie static sound, his body is then gruesomely converted into a Kanshu or suffers irreversible infection. Riku is saved by two warriors, Rena and Youhei, who wield Jinki weapons designed to destroy Kanshu. During the battle, however, Riku finds a cocoon, out of which hatches a toddler looking exactly Riku's dead relative Amane. As the situation goes downhill, Riku ends up receiving his own Jinki and gets drawn into the shadowy organization that fights the Kanshu.
Riku is story's protagonist, is a high-school student who lives with his father (absent for most of the story) and stepmother, Shizuru. He was in love with Shizuru's younger sister, Amane, but she is presumed dead two years ago in a fire. After sustaining, at the start of the series, a fatal wound from a Kanshu, Neene turns Riku into a special Kanshu that can retain his own consciousness as long as he has a Jinki. His Jinki, gained through Youhei's sacrifice, takes the form of a chainsaw-like sword with trigger grip. Despite his desperate efforts to keep Neene out of harm's way and public knowledge, F.L.A.G eventually sets its sights on the young hybrid and puts Riku under custody, only for the two of them to escape with the director as hostage. After the source of infection take Neene he has disappeared. He reappeared in the battle of the rubble tower only to disappear for three months in the aftermath, reappearing in a cocoon of light. In his Jinki form, Riku retains his white hair and markings from his kanshu transformation; due to multiple sightings, the online community has started to call "Suraga".
Neene is a "Coffin Princess" who appears to be a toddler about two years old, but has an uncanny resemblance to Riku's dead aunt Amane. Neene was hatched from a cocoon at the start of the story, and grows at a rapid rate, experiencing a growth spurt triggered each time she uses her powers in a Kanshu fight. As the series progresses, she demonstrates various powers, such as turning Riku into a Kanshu after he is mortally wounded in a fight as well as creating a giant ball of light that disintegrates anything it touches or envelops. She is eventually revealed to be a Kyuki, a queen Kanshu who receives the memories stolen by other "drone" Kanshu, and her growth is directly linked to the absorption of additional memories. She has recently gained more power and is capable of manipulating memories and manifesting wings and has left with the source of infection. During the battle of the rubble tower she fought off ende but was seemingly killed off protecting Riku. Due to her two protectors' close proximity, Neene has started calling Riku "papa" and Rena "mama". After realizing his feelings were for Amane despite her feeling being for him the most important thing. Her last words were "Liar."
Rena is a young Jinki user who is depicted as a quiet and serious person focused on her job, who frequently takes the lead when fighting Kanshus. Her Jinki is Shingetsu, a pair of chakrams with a trigger-like grip that allows the four blades of each Shingetsu to spin. After Youhei's death, she becomes Riku's partner, whom she appears to have become attracted to, after their meeting with the Source of Infection. Later on, it is revealed she is a "lost re-bound" victim; the person who disappeared was someone she considered a mentor. She then had a flood of memories ending with the vision of a masked person. Her hometown was on Hatsumi island, which everyone had forgotten due to a Kanshu attack. She is currently looking for Riku and Neene, who disappeared after holding F.L.A.G.'s director hostage. In the battle of the rubble tower she fought a black kanshu who fought similar to her master. She disappeared with Riku for three months after the end of the battle.
Youhei is a Jinki user and Rena's initial partner. He is depicted as an optimistic and cheerful person. Before the series began, he and Riku met during their stay at the hospital and became fast friends. At the start of the series, Youhei and Rena rescued Riku when he was first attacked by Kanshus. His Jinki resembles a short blade and was given to him by his teacher, to save him from Kanshu-inflicted wounds. In an ironically similar situation, Youhei ends up entrusting his own Jinki to a wounded Riku. At his own request, he is beheaded by his old friend before he could become a complete Kanshu.
- Takao Ryuusei is a Jinki Hunter who seeks Neene's power in order to defeat the elusive Source of Infection. He is a widely discussed mass murderer, having taken dozens - perhaps hundreds - of lives since he became a Hunter two years ago. To aid him in fights against Jinki Users, he uses the captured Jinki cores of past slain users to boost his power tremendously - enough to shatter Cages with a single hit. To top it off, he is highly skilled with his katana. He is in contact with a mysterious person by the name of Julie and appears to have once been betrayed by an individual called Shiro. Even with a ruined hand, he nevertheless remained skilled enough to fight Joe, Clara, Riku and Rena all at once, only retreating when he found out his 'Time' was up. He however doesn't depart without giving riku advice about Neene. In the latest chapter, it is revealed he has met Yui and accidentally wounded her while trying to protect her eventually leading to her death as the rushed to the hospital. His real name is Takao Ryuusei. He's the master of Coffin Princess "Julie."
- Karasawa Shirou is a mysterious figure depicted as the source of Kanshus. Unnamed at first, he appears as a man in a suit wearing a kitsune mask who visits Riku and uses his mask to confuse and recruit the young man. He is the he former director of Flag and uses a special device to access to Flag's computer systems. He has promised Neene that he will help her discover herself and her origins. He uses her power to awaken Coffin Princess "Ende" but was soon killed off by Kazama. His last connection allowed him enough time to beg Neene to stop Ende, who was on a rampage at the Master's death.
- Tougo Kazama is a childhood friend of Riku's. He managed to recognize Riku as Suraga and while being hunted down by Takao, he awoke to a Jinki core. He later explains that two months earlier, during the NEFT building fire, a bright light (one of the Jinki cores from chapter 15 that Takao lost against Riku) came crashing towards him. The glowing scar he retained from the incident disappeared the next morning. His core has a scratch causing him intense pain, and he can't materialize a blade, forcing F.L.A.G. to engineer a customized weapon for his own use. He sniped Karasawa in the battle of the Rubble Tower and has since then spent three months training in Riku's absence.
Main article: List of World Embryo chapters
Written and illustrated by Daisuke Moriyama, World Embryo premiered in Young King OURs in 2005 and is currently on-going. Shōnen Gahosha is publishing the individual chapters in tankōbon volumes, with seven released in Japan as of September 2010.
The series is licensed for an English language release in Singapore by Chuang Yi, in Australia by Madman Entertainment, and in North America by Dark Horse Comics. In Europe, the series series is licensed in Italy by J-POP Edizioni, and in France by Kazé Manga (formerly Asuka).