Biagio Busoni commands authority as a Roman Catholic bishop overseeing 1,000 soldiers, ruthlessly prioritizing the Church’s supremacy even at catastrophic human cost. His pivotal role centers on weaponizing faith: he spearheads the modification of the "Queen of the Adriatic Sea" from a Venice-specific deterrent into a mobile threat against Academy City, an initiative central to the La Regina del Mare Adriatico Arc. Following the weapon’s deployment, he is imprisoned in London Tower alongside collaborator Lidvia Lorenzetti. During the Document of Constantine Arc, Biagio faces interrogation by Stiyl Magnus and Agnese Sanctis. Though physically diminished—cracked skin and dulled hair betraying sleep deprivation’s toll—his unyielding arrogance surfaces as he dares his captors to employ torture, mocking their perceived weakness. Lidvia’s negotiation to exchange secrets for prisoner releases triggers his contemptuous silence, yet he maintains defiance even as she exposes God’s Right Seat’s vulnerabilities. His combat arsenal channels Christian symbolism through crucifixes, wielding multiple necklaces laden with crosses. Spells draw from saintly martyrdom: the St. Margaret’s Crucifix morphs pendants into three-meter spears, echoing the saint’s dragon-scale survival, activated by incantations like *"The Cross reveals the rejection to evil."* The Weight of the Cross amplifies gravity on projectiles to cannonball force, invoked with *"The weight of the Cross corrects the haughty,"* while Simon Carrying the Cross imposes crushing burdens via chants of *"Simon bears the cross of the Son of God."* Visually nondescript, Biagio’s opulent, excessively adorned garments camouflage him among lesser antagonists, a deliberate aesthetic underscoring his role as a bureaucratic instrument rather than a standout figure. His manipulative tendencies emerge in dealings like coercing Agnese Sanctis into humiliating attire during captivity, exemplifying his tactical exploitation of allies. Post-imprisonment, his influence wanes, leaving him confined to obscurity without further narrative consequence.