Disclaimer: I wish.
They have been over it a million times, poring over memories and verses from a book four hundred years old. Rai genuinely seems to prefer the book, whether for its cruel calculations of judgment or its promises to the faithful, Ren cannot decide and Rai doesn't tell. Ren for his part has occasionally seen specials on T.V. on the occult and they use those, too, for all the good that it would do. Rai mocks them sometimes, if not for the melodrama of the programs than for the melodrama their own lives have become, the bitter irony of reality stranger and crueler than anything written, anything fabricated.
One of those specials was about a guitar player from America, who was reported to have sold his soul to the devil to become the greatest blues guitarist in the world. To him was given the gift of a quick and early death, after his records dazzled the country but before he could have the chance to complete a worthy follow-up.
Past that, Ren has to admit he doesn't know of any others, at least not offhand or with any slight basis in fact. Rai shrugs a little, admits it doesn't matter when the truth about such deals stares them straight in the face every day.
And Ren nods, yes, it's pointless, but that doesn't stop them from going over it again and again, the first in a series of useless exercises. They keep them human, those meaningless little things, the dogged determination particular to Man and Man alone, the struggle to survive when hell itself is eager to swallow them up.
So later Ren says that he'll see if he can remember more and Rai says he's never read every bit of the book, anyway; he'll try now. And they're at it again, one last time for one last day like a drug addict's promise of reform, though there is no answer, in either the book or the memories, only a weak, small delay of the inevitable.
For as long as they can continue the studies, the devil cannot triumph.