Siren is a large built man with blond hair that is brushed back and braided. He has narrow eyes and no eyebrows.
He wears a double-breasted and long-sleeved shirt with a high collar and red trimmings on the edges. The collar also has a chain connecting both ends of the collar as an ornament. The shirt itself is made of two different colors where it is white at the side and red on the middle. The sleeves are mostly in white fabric, except the wrist area where it is red fabric. The shirt extends below his waist and Siren also wears a light-colored sash on top of it. Furthermore, Siren also wears a casual white pants and a pair of high boots to complement it. The black boots also have fur around the collar.
Siren wears the Golden Dawn's signature squad robe, which covers his torso and is gold in color. The fabric has an intricate design with a similar color palette as the robe. It also has a blue-colored fur around the border of the hood and a pair of blue ropes coming from the left shoulder and connected to the gold-colored button on the right shoulder. The button keeps the robe properly in place. The squad's insignia is positioned at the left-hand side.
Siren is a calm and silent individual who does not talk unless it is necessary.
Much later, at a decoration ceremony Siren is promoted to a 1st Class Intermediate Magic Knight by the Magic Emperor. Soon after Julius leaves, some of the Magic Knights begin to scrutinize the unwanted guests, but Siren does not take part or say a word. Once the capital is under attack, Siren uses his rock magic to create a living model of the capital. The Knights analyze the situation before Fuegoreon Vermillion orders the Golden Dawns to split up and protect the Royal Capital's Northwest and Eastern Districts. Siren then rides with Hamon Caseus and Klaus Lunette in Klaus' steel chariot.
After Siren, Klaus, and Hamon defeat the corpses in the Eastern District, a Spatial Magic spell activates and transports them and several other Magic Knights far away from the city. The stranded knights combine their magical power together to create a compound spell that quickly carries them back to the Royal Capital. The White Night Eyes retreat upon seeing the Magic Knights return.
Once the enemy leaves, Siren helps restore communication and reinforce the magic wall. After the Magic Emperor returns, Siren listens as Julius tells them what happened. When everything is done, Siren returns to the Golden Dawn headquarters.
Several months later, Siren is enlisted into the Royal Knights for his mana-sensing ability. After the squad travels to the Gravito Rock Zone, Siren models the interior of the floating dungeon, and Mereoleona Vermillion explains the situation before dividing the squad into teams. Nozel Silva infiltrates the dungeon with Siren, En Ringard, and Nils.
- Enhanced Mana Sensory: Siren can sense all of the mana within a large city.
- Grimoire: Siren possesses a grimoire that contains various rock-based spells. His grimoire has checkered covers.
- ↑ 1.0 1.1 Black Clover Manga and Anime — Chapter 23 (p. 5) and Episode 20.
- ↑ Black Clover Manga and Anime — Chapter 2 (p. 14-15) and Episode 4.
- ↑ Black Clover Manga and Anime — Chapter 23 (p. 8) and Episode 20.
- ↑ Black Clover Manga — Chapter 24 (p. 18-20).
- ↑ Black Clover Manga — Chapter 25 (p. 7-13).
- ↑ Black Clover Manga — Chapter 28 (p. 4-11).
- ↑ Black Clover Manga — Chapter 34 (p. 12-17).
- ↑ Black Clover Manga — Chapter 36 (p. 10-11).
- ↑ Black Clover Manga — Chapter 36 (p. 13-17).
- ↑ Black Clover Manga — Chapter 134 (p. 14).
- ↑ Black Clover Manga — Chapter 135 (p. 1-4).
- ↑ Black Clover Manga — Chapter 135 (p. 13).
- ↑ 13.0 13.1 13.2 13.3 Black Clover Manga — Chapter 25 (p. 8).