Hikawa is the head of a communications company and a major secondary character in Shin Megami Tensei: Nocturne. He is also secretly the leader of the Gaea cult, and it is in this position that Hikawa learns of the Scripture of Miroku, a forbidden and dangerous text. The prophecies within the scripture lead to his desire for a new, cleansed world, and it is because of this desire that Hikawa brings about the Conception; an event that returns the world to a blank slate to be molded by a new philosophy. This new world is the Vortex World as foretold in the Scripture of Miroku.
After the Conception, the demons that populate this new world do not suspect Hikawa as the source of its creation, but rather blame the Assembly of Nihilo. Because Hikawa escapes blame, he is able to form his Reason "Shijima." This philosophy allows Hikawa to discreetly carry out his plans to create his ideal world; an ordered world without anarchy, flaws or disagreement. However, his plans hit a snag when he realizes that other humans have survived the Conception, and are thus capable of forming their own Reasons. His greatest concern, however, is the Demi-Fiend who, though unable to create a Reason of his own, has the power to significantly affect the outcome. Hikawa thus attempts to court the Demi-Fiend to his side in order to see that his dream of realizing Shijima isn't foiled.