Jean Luc LeBlanc, a high-ranking French operative within the shadowy organization Alchemy, serves as Lieutenant Commander and second-in-command aboard the space station *Watcher’s Nest*. Publicly posing as Professor Je Labelle, he covertly spearheads the revived Kessler Project, experimenting with hybridizing human subjects with Ghoul DNA to unlock extradimensional powers tied to these cosmic entities. Genetically engineered by Alchemy as a test subject—and sharing a lineage with Prim Snowlight, a fellow project figure—LeBlanc obsessively pursues transcendence beyond humanity. His goal: to shed mortal constraints through fusion with Ghouls, attaining an ascendant state of "utter nothingness" while wielding their unfathomable knowledge. Ruthlessly pragmatic, he orchestrates events from the shadows, deploying microchips to manipulate allies like the hybrid Misaki Kureha and sacrificing subordinates without hesitation to further his ambitions. Though outwardly composed, even smiling amid calamity, his calculating demeanor fuels distrust among peers like Lyar von Ertiana, who openly condemns his moral compromises. In his final gambit, LeBlanc merges with a Ghoul, only to disintegrate under the strain of its cosmic consciousness. Yet his machinations ripple beyond death—collapsing the Inflation Hole network, destabilizing spacetime around *Watcher’s Nest*, and exposing humanity’s precarious link to Ghoul-related dimensions. His legacy endures as a catalyst for chaos, forever altering the struggle between scientific ambition and cosmic horror.