Beatrice

Beatrice is a Witch, a major character in Battler's backstory, and a minor character in Off-Season 2 and Season 3.

Beatrice, The Golden Witch
Beatrice is determined to prove to Ushiromiya Battler that the murders committed in the Rokkenjima Incident were the cause of magic, and will fight against Battler's theories as many times as it takes to prove it.

Off-Season 2
Beato arrived to Cope Island to continue being a rival to Battler.

Season 3
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Trivia

 * Beatrice's name is pronounced the Italian way, as "Be-a-tr-ice" (Be-a-to-ri-che [ベアトリーチェ] in Japanese phonetics) rather than the English way, as "Be-a-triss".