Denji and his pet devil Pochita strive to pay off the debt that his father’s passing left him with. Denji is killed by the yakuza, but Pochita merges with his corpse and emerges as a Chainsaw Devil. Denji is brought in to hunt other devils on an experimental squad after being discovered by government devil hunters. Here, he is finally able to follow his simple teenage fantasies of enjoying delectable food and spending time with a pretty female.
Demons look for pieces of the legendary demon Sukuna to ingest in order to gain more strength. When his schoolmates breach the seal on one of Sukuna’s body parts that was at their school, Yuuji Itadori, who recently lost his grandfather, finds out about this while saving them from demons. He consumes it in order to give himself a chance, showing himself as a unique vessel that can harness and control the curse of Sukuna, which means that when he passes away, Sukuna’s curse passes away as well.
A random guy uniting with a devil, gaining a ton of power from it, and joining an organization that hunts those monsters are fairly similar plotlines in both series.
Akira volunteers to assist his boyhood friend in finding devils because he has always been a little weak and blends in. The two travel to Sabbath, where a large crowd congregates for revelry and demonic possession. Akira consents to merge bodies with a devil as the devils start wreaking havoc in their new living hosts in order to save his friend. He now harbors a ravenous devil, yet his heart is still that of a whiny child.
Both Chainsaw Man and Devilman Crybaby are about young men who, as a result of an incident, discover that they have been fused with a devil while keeping control of their selves. Additionally, they both happen to be anime programs that enjoy a good gory spectacle.
Ajin, immortal people, originally appeared in Africa 17 years ago. Despite being considered a menace to humanity, they were often only a passing news story to many. Kei Nagai, a high school student who is working hard to become a doctor, learns he is an Ajin after being fatally struck by a car. Kei must find a method to survive as he is now on the run from the government, which intends to imprison him.
Both television shows revolve around characters who discover, either after being turned into demons or after having been one all along, that they are, in fact, demons. This makes them targets for government agencies, but Ajin stands out since he makes an effort to avoid them.
After being abandoned by his parents, a child with the moniker Dorotabo now resides with his aunt in a small Japanese inn. Kohachi Inugami, a detective from Tokyo who specialized in the occult, shows up one day. He shows interest in Dorotabo while conducting an investigation into a mystery livestock fatality. After assisting Inugami, the youngster learns that he is only partially human. Inugami takes him back to work at his agency in Tokyo since he is skilled at eliminating beast-like beings known as Kemono.
Kemono Jihen has a visual style that makes it appear younger, yet unlike other shounen series, it isn’t shy of gore.
Yoma are a race of demonic beings that relentlessly torment humanity. After Yoma killed Raki’s parents, he joins forces with Claire, a Claymore, a group of strong half-human, half-Yoma women who are despised by society but strive to eradicate Yoma. Together, each person discovers more about the other and advances toward their own objectives.
In each stories, there are characters tasked with tracking out demons who have been infused with them. Since the slayers are all female and will eventually change into demons that the following Claymore generation will have to go kill, Claymore is, nevertheless, a little more depressed about it.
Shinichi Izumi, at sixteen, was sound asleep one night when a race of parasite aliens landed on Earth. Shinichi contracts a parasite that tries to enter his brain to take over his body but instead gets lodged in his right hand. The alien, known as Migi, is unable to migrate to the brain and must now learn to coexist with Shinichi in order to survive. Unfortunately, neither humans nor parasites that have failed in their goal are particularly nice to the other parasitic aliens.
While not about joining forces with a demon, Parasyte depicts a character joining forces with an alien to create a partnership that benefits both parties.