Lagen supported and contributed with the assassination of Hector and is a main antagonist. He wants to rule Sana and is very manipulative. He was the one who pushed Belca off of the cliff. Lagen conducts experiments on the Amontel and is the son of one of the Elders. He wants to vanquish the Elders and not much is known about him or his past.
Orcelito Noctircus is a supporting character and was the second prince in line of the throne. Since his older brother Hector was assassinated, he is now in line of the throne. He is much more serious and mature than both Hector, Musca, and Belca but he is also soft spoken. He often admonishes Musca for badmouthing Belca and his heritage-especially his mother. He loves both Belca and Hector and he too, discovered the conspiracy but is kept quiet and is also locked up by Lagen. He was threatened with the life of Musca and couldn't do anything so he now cooperates with Lagen and the Elders. It was revealed that he is actually an accomplice of Lagen later in the manga, showing a more dark and twisted side of him but still caring for his beloved siblings. (Source: Wikipedia)
The best friend of Rose Dupré. He later on goes on to become a hunter after discovering that Rose is the witch, who is otherwise known as the the Pale Horse. Also, dissolving all relations and emotions he felt for her.
Twining family butler. His family served the Twining family for generations. Actually, his true name is Uriel, the angel of Repentance and Cruelty. It's shown to have just a wing because the other was taken by the archangel Michael.
The Western Duke and leader of the Anti-Nephilim faction, he chose Sitori as his candidate for substitute king. Although Sitori is his nephew, he treats him poorly and was the one that caused Sitori to become a demon.
Solomon's 15th Pillar, whom commands 60 legions of Hell.