Description
Claude Sirius stands as a first-class sorcerer celebrated for his extraordinary magical talent, achieving the unprecedented feat of becoming a Royal Diana Academy of Magic professor at seventeen – the youngest in history. His abrupt disappearance two years before the main narrative stemmed from a curse cast by the terrorist cult, The Black Serpents, during their assault on the academy. This curse permanently transformed him into a black cat, drastically reducing his magical capabilities in this feline state.

Discovering Spica Virgo, an aspiring witch possessing latent Rebirth magic, Claude forms a pact: he pledges to mentor her in magic if she aids him in breaking his curse. Spica's unique magic can temporarily restore his human form each morning, though the process demands a kiss in an unconventional location. The duration of his human state relies entirely on Spica's remaining mana reserves. Achieving a permanent cure necessitates Spica attaining magical power equal to his own, fueling his dedication to her rigorous training.

Claude embodies a complex mix of arrogance, pragmatism, and concealed protectiveness. Frequently blunt, sarcastic, and impatient – particularly with Spica's early struggles – he fits the "jerk with a heart of gold" mold. Beneath this abrasive exterior lies fierce loyalty; he confronts threats like Arc or Rigel of The Black Serpents without hesitation to defend his students. His past actions during the cult attack, deliberately drawing Arc's fury away from students, reveal his selfless core, though this initially fostered misunderstandings that damaged his standing with peers such as the Gemini twins.

Magically, Claude commands Sagittarius magic, specializing in wind manipulation and ice conjuring. Even cursed, he retains limited spellcasting capacity. When fully recovered, his power proves formidable enough to overcome adversaries like Arc and Rigel. He ranks among the setting's mightiest sorcerers, surpassed only by his former mentor, Jeanne Orion.

His character arc revolves around his evolution as a mentor. Tasked with instructing his eclectic class, "Claude Coven" – nicknamed "Pandora's Box" – he shifts from a reluctant teacher to a deeply invested guardian. His bond with Spica strengthens through their shared curse-breaking mission, though he remains unaware of her romantic feelings. Flashbacks illuminate his fractured history with his former ally, Arc; their rift originated from her belief in his betrayal, though he was ultimately cleared. These experiences underscore themes of sacrifice and redemption throughout his journey.