The devil is a little nicer than Nathaniel. Let's just say, he's been around for a while and will be around long after the Eternity Clock stops...
He is the one who set Rosalyn Smythe on her current course of destruction and mayhem. She may have thought he was helping her out, but she is only one of his helpless pawns.
Nathaniel will stop at nothing to achieve his goals. His sites are also set on Bryce, Sebastian and Jade. But, what is it he's really after? Only time will tell...