It should be clear why Shingeki no Kyojin is my first choice. If you haven't seen this anime before, you should watch it right now! Nearly a century ago, mankind was almost annihilated because of the sudden appearance of Titans, giant creatures who kill humans for pleasure and not really because they need to eat. To protect themselves from this threat, survivors built three concentric walls, big enough to prevent every Titan from coming in. Every wall was named and are distant by thousands kilometers each. As peace had finally settled, one day, a Titan of 60 meters appears and opens a hole in the first of the three walls. Which allowed a dozen of other Titans to enter the little town where the main character, Eren Yeager, and his friends, were living. After seeing his mother been devoured by one of the Titans, Eren decides to enter the Survey Cops, the military force against Titans, in order to take revenge. In this series, you have the classic fight against monsters who eat humans that you can find also in Claymore, but not just that. There are a lot of mysteries beyond the military force and also beyond the existence of Titans itself. The bloody and stressful scenes will remind you of the atmosphere in Claymore, so I really recommend this one!

In the peaceful city of Tokyo, anthropophagous monsters called Ghouls appeared, committing crime after crime. As they are living amongst humans, a special police force is settled in order to track and eliminate them. The story follows Ken Kaneki, an ordinary college student. In a coffeeshop, he met Rize Kamishiro and fell in love with her. As they going out one day, Ken realizes that Rize is actually a Ghoul who manipulated him in order to eat him. While torturing the poor Ken, Rize is suddenly killed by accident and dies. In critical condition, because of all the wounds he received, Ken receives transplants from some of Rize organs at the hospital. Because of the transplant, Ken becomes a hybrid half-human, half-ghoul, and has to fight his human meat hunger. Fortunately, he will find help in the coffeeshop, “Anteiku”, and learn how to live with his new abilities. This one is really interesting because the main character becomes a hybrid of what humans are the most afraid of. Because of that, it will discover what are really Ghouls and how some of them aren't so different from humans. Like in Claymore, you can see the perspective from another side than the human's one. The fighting scenes are pretty bloody and some characters are really disturbed. The story is as deep as Claymore's and there is a lot of turnarounds.

Saya Kisaragi is a high-school student who, despite of being really clumsy, seems like an ordinary young woman. She lives with her father in a shrine and learns swordsmanship. What Saya's friends are ignoring is that she is more than a simple young woman. After school, at night, she has a particular mission and armed with her sword, she goes fight against creatures called “Furukimono” (or the “Ancient ones” in English). They are mysterious monsters who attack and terrorize humans in the little town. Saya fights against these creatures along the series, but she begins to wonder about her duty and even her own identity. The mysterious and psychological aspect is pretty similar to Claymore's. Saya's past is unclear and as you watch this series, you realize that the story is deeper than you can think.

Ten years ago, a mysterious area appeared in the city of Tokyo, destroying everything around and even distorting the sky. Because of this area, called Hell's Gate, fake stars appeared, replacing the real ones. Afterwards, individuals with supernatural abilities began to appear, each of them strangely linked to each of the false stars. These people, named “Contractors”, are nowadays living amongst humans and are mostly used by governments as murderers or spies. Each time a Contractor uses his power, he has to pay a price in return. According to each person, it can be a simple diet change or a radical physical change. Hei is a Chinese Contractor in mission at Tokyo. He is under the orders of a mysterious organization called the Syndicate, which also controls Dolls, beings created to mimic humans. This series isn't as bloody as Claymore's, but it's still quite violent in some parts. Contractors are more logical than humans and almost emotionless, which is why they are interesting. The Syndicate is said to have no apparent objectives but, like the Organization in Claymore, it isn't that simple and there is a lot of mysteries beyond.

Ranmaru Shindo lives in Tokyo with his little sister, Saya. Because of the dead of his parents five years ago, Ranmaru decided to join the police force Tokki, in order to find out what really happened that day. The day of his graduation, he meets Sakura Rokujo, a young woman, also part of the police force. When he sees her, he realised she is the woman he dreams of every night, armed with a sword and covered in blood. Sakura Rokujo is part of a special unity called Tokko, on which rumors are saying members aren't even humans and responsible for horrific events. During his investigations, Ranmaru will discover the truth beyond the tragedy responsible for the death of his parents, which is directly linked with the existence of Tokko's unity. If you liked Claymore because of the monsters and the bloody scenes, this series is for you. Members of Tokko can be assimilated to Claymores because of their abilities and strength to fight against demons.

In the near future, in Germany, “Demoniacs” are bio-mechanical creatures taking possession of corpses and attacking humans. Demoniacs have the ability to merge with any mechanics in order to evolve and become stronger. An unity force, the Xenogenesis Assault Team, also known as the XAT, aims to prevent any threat from them. During a motorbike Grand Prix, a Demoniac attacks and wreaks havoc on its way. Before the XAT could get in place, a mysterious man known as “Blue” destroys the Demoniac, saving the life of Gerd Frantzen, a famous motorbike champion. Gerd becomes a paraplegic because of the attack, he is offered a miraculous cure which saves him, but makes him become a hybrid. Because of this new status, Gerd will be under the surveillance of the XAT. In this story, because of the threat represented by Demoniacs, there are some appearances of humans turned into Demoniacs. Some of them are not able to control their powers and like in Claymore, you can find almost the same concept of “awakening”. With the different arcs, the story follows a lot of characters and help you understand how deep and dramatic the concept can be.