"I am getting there. Eventually, this fragment concluded it needed a human will, as if it tried to use its own will, it would disappear in the whole. But interfacing a human will directly into Nyx was nearly impossible. If only there could be a link, something compatible with both humans and Nyx..."

Ken's smile got a little wider.

"You know what I'm talking about. Shadows. Coming from Nyx herself, and present in all humans. But to relay the human's will to Nyx, the Shadow needed to be under its host's control. It needed to be a Persona."

Ken then sighed, and looked slightly pensive.

"And so the fragment looked for someone who both had the will to end the world and a Persona. A stable one, as the connection with Nyx would cause enormous strain, so Strega couldn't cut it. It searched, and it searched, for years."