Demon Card is a major organization who uses the dark powers of the Dark Bring to bring evil and violence in the world.
The Demon Card is an organization who makes their name widely known, so people feel fear and timidness when they hear their name. Demon Card is created when Gale Glory and King Raregroove meet each other to combat the demons on the converging day. The name that Gale proposes, Demon Guard, is changed to Demon Card. They appear in different groups, and all look different, but have the same purpose or goal. Most of Demon Card use Dark Bring as their primary weapons.
Dr. Schneider is an assassin hired by Shuda.
Lance is a general or a captain (not clear in the series) due to his authority over his henchmen and Punk Street. Go will also fit in this category as well.
The Five Palace Guardians are King's men who attack Haru and his gang during the Tower of Din Arc. King summons them using a Dark Bring, Gate. In the anime, they are introduced in episode 30 and all of them are defeated in episode 33.
They are the top six generals who use the Six Star Dark Brings. Even though King uses Overdrive on Demon headquarters, the Oracion Seis survives and takes orders from Lucia Raregroove. Former members are Shuda and Sieg Hart which are replaced by Deep Snow and Haja.
King (Gale) Raregroove is the head of Demon Card. After his death during the Tower of Din Arc, his son Lucia Raregroove (who was presumed dead) takes control of Demon Card and the Oracion Seis. Both father and son wield the Decalogue Sword.