Rasiel (also called Siel) is Belphegor's older twin brother and possesses the Fake Storm Mare Ring. He and Belphegor fought constantly as children, but he always won; so, to beat him, Belphegor put laxatives in Rasiel's food to incapacitate him; on the other hand, Rasiel fed his brother with worm-ridden mud. He has blond hair that is longer than his younger brother's, and instead of using Storm Boots like Nosaru and Tazaru, he uses a Storm Throne to fly. He has a crescent-shaped birthmark on the left side of his stomach which mirrors Belphegor's. Rasiel also wears black nail polish.
Originally thought to have been killed by Belphegor, Rasiel reveals himself as the one responsible for the Millefiore defense in Italy and can unleash Bats from his Box Weapon that can emit invisible Storm Flames to harm his enemies. His personality is no different from Belphegor's, except that he states that he is a king rather than a prince. He is accompanied by his Family's former butler, Olgert, who claims to only follow the one who would be king and can unleash a Rain Pelican and Heavy Rain Elephants from multiple Boxes. Rasiel and Belphegor start their battle, but Belphegor is forced to Fake his death with the help of Flan. After the battle, Rasiel confronts Xanxus, but is overwhelmed by his Box Weapon, Ligre Tempesta di Cielo. Before Rasiel and Olgert are destroyed by Bester's roar, he made a deal with Xanxus that Xanxus can become the Boss of the Vongola if he sides with the Millefiore but was rejected. It has been revealed that Byakuran gave Rasiel a Fake Mare Ring and that he is not one of the Real Six Funeral Wreaths.
He is accompanied by his Family's former butler, Olgert, who claims to only follow the one who would be king. At this point, it seems that Olgert can unleash a Rain Pelican and three Rain Elephants from multiple Boxes. He has a Rain Attribute Flame and uses Rain Boots to fly alongside Rasiel.
Rasiel and Belphegor have had a worsening relationship from the time of their birth. The situation's severity escalated over the years until Belphegor eventually murdered Rasiel when they were 8. Rasiel doesn't care for his little brother's well-being at all, a feeling which is mirrored in Belphegor. When Rasiel reveals himself to Belphegor, their twenty year old rivalry and hatred surfaces immediately, showing that even after two decades and one's purported death, they cannot get along.
Weapons and Abilities
- Storm Throne - A Throne suspended in air by Storm Flames.
- Pipistrello Tempesta lit. Storm Bats - Rasiel uses these to emit sonic waves against his opponent, that enters in their head from the ears and kills them.
- Knives - Rasiel is also known using knives like his twin brother, since he was a kid.
- He thinks very highly of himself and says "ore-sama" when referring to himself, which translates to "my honorable self."
- He has a similar laugh to Belphegor; however, instead of "ushishi", Belphegor's laugh, it sounds like "usheshe."
- Rasiel and his twin brother Belphegor share the habit of saying "Kaching" when angry or annoyed with someone. Bel says it to Flan when the latter throws away Bel's knives, and Rasiel says it to Xanxus during their fight; however, they seem to be unaware of this shared trait.