Saint is a high-ranking Vatican official orchestrating covert scientific and military operations. Tasked with overseeing classified experiments—from genetic engineering to biological weapons—he coordinates with military and ecclesiastical entities under Vatican mandate. His responsibilities include monitoring Dr. Kyoji Ogami’s research into extraterrestrial DNA and the regenerative properties of GREEN, a subject central to a clandestine resurrection initiative.

When crises emerge, such as an alien organism’s mutation sparked by Nanako’s presence, Saint sanctions lethal containment measures, adopting a pragmatic stance to preserve secrecy. He relays developments directly to the pope, highlighting the Vatican’s deep investment in these projects and their capacity to shape humanity’s trajectory.

Saint collaborates with figures like David Griffith, a military scientist, to evaluate Nanako’s potential as a catalyst for human evolution. These interactions underscore his strategic role in covert conspiracies seeking to weaponize scientific breakthroughs for hidden agendas. His decisions often hinge on balancing operational security with long-term objectives, prioritizing containment and data acquisition above ethical concerns.