If you liked the Chrono Crusade manga, the Anime-Planet community thinks you'd like:
In the modern world most people live ignorant of the supernatural. Vampires exist with superhuman strength, speed and regeneration; they can control humans with a gaze and control their will for eternity by feeding them blood. Kuroe is a man whose calling is vanquishing vampires. His will, the legacy of his name and a vampire's curse give him the strength to hunt the one responsible for the loss of his sister. Yet he lives to atone for his mistakes. Misaki is a new vampire who was recently turned after Kuroe was unable to protect her. Now she lives under his, protection and in passing they calm each other's wounded hearts. Under reoccurring vampire threats the two grow closer together and develop an enticing bond.
Fighting the creatures of the dark is only their job, until they find out more information on the people they are trying to find. But why are Kuroe and Rosette looking for these people? Is it because of something from their dark pasts? Or is it because of something else?
The first law of alchemy is that "one cannot gain something without giving something of equal value in return" - a rule that two souls dare to cross. When Edward and Alphonse Elric try to revive their dead mother, breaking the taboo of human transmutation in process, Ed loses his right arm and left leg while Al loses his entire body. After the tragedy, an alchemist named Roy Mustang visits them and tells Edward to become a state alchemist to find a way to recover what they have lost. Accompanied by Al, whose soul is now attached to a metal suit of armor, Ed is fitted with auto-mail parts in place of his lost limbs and becomes a state alchemist by the name of "Full Metal Alchemist." Together, they set forth on a journey to find the Philosopher's Stone - the one item that is rumored to have the power to restore them.
Both series are set in a world of magic and science, and the 1920's setting (with a bit of steam punk) in Chrono Crusade meshes well with the fictional world of FMA. Both also have great, streamlined art that allows you to tell what's going on during the action scenes, and get caught up in the dramatic moments. These series can be both very dark and very comedic at times, sometimes philosophical. Personally I think that CC is focused more on the character relationships (particularly Chrono and Rosette and those close to them), while FMA has character relationships serve as a backdrop to the adventure, but both are wonderful series and absolutely worth the look.
Five hundred years ago there lived a feudal lord with a vast amount of spiritual power. To keep it from falling into the hands of demonic Ayakashi, the mage Tokimori Hazama and his two students were called to defend the land. However, they fell ill, and the feudal lord was killed and buried on the land now called Karasumori. Years later the successors of the Hazama students, Yoshimori and Tokine, have inherited the powers of the Hazama clan. They are Kekkaishi, users of the Kekkai, a secret and powerful technique that creates a strong barrier to capture and eliminate Ayakashi. Protectors of the power buried beneath Karasumori, Yoshimori and Tokine spend their days in the school built on the land, and their nights defending it from attackers who wish to use the power for their own purposes. With Karasumori's power growing more unpredictable everyday, will Yoshimori become strong enough to protect the ones he loves?
Defeating demons isn't as easy as it seems when you don't really have that much determination to fight them, so why do Yoshimori and Rosette fight these demons when they don't have the determination to fight them? Is it just because it's their job? Or is there another reason?
Both of these series deal with relations between super natural creatures and the catholic church. Friendship and coexistance between species is also a big theme. People may not take Chrono Crusade seriously at first due to its comedic nature at first, but it gets serious in the later volumes.
Both of these manga are written by the same guy, and it really shows. Although the plots are very different, there's similar characters, plot twists, relationships between the characters, and themes. In particular, Moriyama seems very concerned with exploring how people relate to each other, and how "families" can grow in hardship. It's hard to go into them without spoiling too much, but they're definitely similar, and I think fans of one could easily become fans of the other.