Mana-lith

This world takes place on a modern version of Earth with an alternate history, where the nations of the world are relatively intact though there are differences. The people of this world are almost all humans of every possible ethnicity, but all of them also have a bloodline sequence of DNA from distant ancestors that determine what abilities they have. Pure humans are exceedingly rare. These bloodlines can be from a number of ancient races, from Elves, to Vampires, to Elementals, Celestials, and Demons. Other bloodlines are a result of a blood-blessing from a God, as is the case with werewolves. Some are extremely powerful like Vampires, others are barely any different from humans like Elves.

Demons, ghosts, poltergeists, aliens, undead, dragons, and more...unspeakable things, inhabit this world as well. Many universes have a secret organizations of some sort that deals with these things. There are worlds with rumored Men in Black Suits that deal with alien scum, there are entire divisions of police forces that deal with undead beings. There are various foundations and organizations that deal with demons, and barely explainable phenomena, keeping humanity from the threshold of insanity and collapse. This world is no different, and has several sister organizations spread across the world to investigate anomalies and defend humanity from them.

In America, they are known as the D.D.D. Foundation (Determine, Detain, Defend), and do, exactly what their name says. They invesitgate anomalies and reports of inhuman activity, then they deal with them. Their primary mission is the defense of humanity. In England, they are known as the Agency. In Europe, they are known as the Organization.