Dr. Giovanni, originally the captain of Special Fire Force Company 3, secretly served the White-Clad cult, dedicated to causing a second Great Cataclysm. His lineage stretched back centuries, his ancestors collaborating with the Joseph clan and Haijima Industries' founders to build the Amaterasu Generator. Giovanni prolonged his life unnaturally by transferring his consciousness into younger bodies using parasitic insects, patiently awaiting the world's engulfment by Adolla. In his past, he apprenticed under Vulcan's grandfather alongside Vulcan's father. Both master and fellow student horrifically combusted into Infernals the very day Giovanni left their workshop. He later joined Haijima Industries, leveraging his influence to blacklist Vulcan from suppliers and cripple the inventor's progress. Giovanni maintained a disguised appearance, typically concealed in a plague doctor mask, top hat, and heavy clothing. Upon revealing his White-Clad allegiance, he adopted a distinctive white trench coat adorned with cross patterns. Subsequent radical self-modifications transformed his physiology into a swarm of fire bugs, abandoning his human form entirely. His personality blended scientific curiosity with ruthless ambition. As Company 3's captain, he feigned concern for the Tokyo Empire's security while secretly planning experiments on individuals like Shinra Kusakabe, possessor of the Adolla Burst. Once exposed, his fanatical devotion to the Evangelist became clear, dismissing human life as expendable. He manipulated subordinates like Lisa (Feeler) through threats and psychological control to ensure obedience. Giovanni wielded Second Generation pyrokinesis, manipulating existing flames and operating concealed mechanical gadgets like projectile hands with heated wires. His intellect facilitated complex inventions such as tasers and hidden weapons, though these proved fragile. After extensive self-experimentation, he integrated fire bug traits, gaining compound eyes for enhanced perception, insectoid limbs, and the ability to disperse into swarms to evade damage. This transformation enabled an artificial Adolla Link for communication. He also perfected consciousness transference via parasitic bugs, later seizing control of Yū's body. Key events saw Giovanni orchestrate an attack on Vulcan's workshop to steal the Key to Amaterasu. He shot Vulcan's apprentice Yū to coerce compliance and destroyed cherished equipment. Though temporarily thwarted by Company 8, he delivered the Key to the Evangelist. Later, he ambushed Vulcan and Akitaru Ōbi in the Nether, forcing Lisa to fight them. He attempted to coerce Vulcan into killing Obi via hostage negotiation, but failed when Obi wore protective gear. Giovanni subsequently lured multiple Fire Force companies into a Nether trap, confronting Shinra in his insectoid form with heightened abilities. After his original body sustained critical damage, Giovanni transferred his consciousness into Yū, manifesting stitch-like marks across the host's face. In this new form, he continued advancing the White-Clad's objectives, his humanity further eroded as he embraced his insectoid nature.