Magic Users, also known as Sorcerers, are a biologically distinct race from humankind. They have a separate organ network in their bodies that can produce smoke, the source of their powers. Aside from their smoke-producing organs, however, they are identical to humans.
Due to their natural abilities, many Magic Users consider themselves to be above humans, and see humans as nothing more than practice targets for improving their magic. Conversely, many humans see Sorcerers as a cruel tyrannical race. However, there are still some Magic Users who see humans as friends or equals, with marriages between Magic User and Sorcerer not being unheard of.
Thousands of years ago, the first Devil, Chidaruma created the Magic Users to ease his boredom. His initial draft of Magic Users looked like nothing more than mud-like creatures with no feet, but then slowly evolved into a more humanoid appearance, eventually coming to look near-identical to them.
Chidaruma then created the Sorcerer's World as their realm to live in. As all Sorcerers are of his creation, all of them automatically go to Hell when they die.
The key aspect that separates them from humans is their unique ability to produce magical smoke. Magic Users have organs that allow them to pump magical smoke through their hands and sometimes their mouths. Almost all Magic Users can produce smoke, some in smaller quantities than others, with the only known exception being Risu, whose Curse magic only works after death, leaving him completely smokeless until that occurs.
Magic Users are very segregated based upon their magical ability. Many of the elites of the magical world are very powerful business owners, including the En Family, which has some of the strongest Magic Users around. On the other hand, the less powerful ones are very poor and many have resorted to joining the Cross-Eyes to gain access to the mysterious Black Powder that amplifies ones magical capabilities.
In general, there are two categories that distinguish a Magic User's power level:
- Volume of Smoke - The amount of smoke that one can produce is probably the greatest factor in determining one's magical worth. The weakest magic users, like Fujita, can practically produce no smoke at all, while the strongest magic users, like En, can produce enough smoke to affect an entire city.
- Type of Magic - There are many different types of magic in the world of Dorohedoro, some very rare and some very common. The En Family has acquired many rare magic users, Kikurage, who uses revival magic, Noi, who uses healing magic, Chota, who uses dispelling magic, as well as many others. It would seem that the most common types of magic are transformative in nature or purely destructive, and anything else is typically on the more rare side of things. The rarest magic of all is Nikaido's time-based magic.
A Magic User has a weak point. If the sorcerer gets hurt there it's possible he will become unable to use magic. The smoke he should be able to discharge through his fingers is not being created as usual.
The special organ that is essential to the Magic User physiology is the mysterious Devil Tumor.
The Devil Tumor, which is located in the brain of each Magic User, seems to house the soul of its owner and their unique magical ability. When Kikurage revives somebody, she is actually reviving their Devil Tumor. The Cross-Eyes' Boss has a technique in which he steals Magic User's Devil Tumors and implants them into his own brain, thus gaining their ability. This is doubly painful for Magic Users, because it makes the Boss harder to kill and reviving their friends impossible. If the Devil Tumor is destroyed, the Magic User will die and reviving them will be impossible.
The Magic Users are a very spread-out race with little to no ruling authority. The closest thing to a ruling body they have is the En Family, that basically controls the majority of the Magic User world with powerful hitmen and various henchmen. However, there doesn't seem to be much-written law and the strong predominately control the weak. As a result, some weak magic users have grouped together and learned fighting skills outside of magic and formed the Cross-Eyes group, which is the counter-culture group against the En Family.
While En's ruling is almost absolute over the magic world, the Devils are the true power in Dorohedoro. The most basic rules of the magic world are 1) Don't cross En and 2) Don't cross a Devil. Besides their omnipotent leader Chidaruma, the Devils are a race of transformed magic users with supposedly limitless power. The Devils don't often interfere in mortal business, but they maintain the jail facility, Hell and they create much of the culture and tradition in the world.
One of the traditions of Magic Users is to wear a mask. Masks can strengthen a magic user's abilities, and higher quality masks carry more power. Less skilled magic users tend to have cheap, store-bought masks, while the wealthy magical elite wear masks made by devils.
Devils can make personalized masks in exchange for gifts. For example, Fujita presented a box full of mummified pixies, but the devil rejected it and punished him.
In the world of Magic, it is a common practice to establish a bond between two individual Magic Users who then become partners.
A partnership can be established every four years on the Blue Night, which is a festival conducted by En and the Devils. The process to become a partner is simple. Two partners find each other and sign a contract, after which a Devil opens their hearts and the Magic Users insert their contracts into each other's hearts. This can either be done willingly or forcibly; if forced, the one who forced the contract onto the other can change the personality of the receiver to make them more docile. The contract lasts four years until the next Blue Night.
- Magic Users experience detrimental physical effects when exposed to Hole's rain. This ranges from headaches to full-body pains and fevers.
- Due to the nature of Hole's rain coming from the Lake of Refuse, a cesspool of human resentment against Magic Users since the beginning of time.
- Half-Magic Users are not as affected, though enough quantities can still affect them.
- It appears that typical naming conventions with Sorcerers align with Japanese names. All natural Sorcerers in the series have Japanese names (with the exception of Turkey, though their name may be a nickname), and Ai points out to Dr. Kasukabe that his name sounds like a Magic User's; he was, in fact, married to a Magic User and took her name.
- Conversely, all non-Magic Users, such as Vaux or Thirteen, have non-Japanese names.