Ronan, I haven't plotted much with! He is not on the Null hit list, but he could possibly supply weapons to those who need it. He could probably use his abilities to create weapons capable of piercing the Null armor, but if left to his own devices, he'd likely just summon crazy fucked up bird monsters to take flight and help him and Adam.

Rome, I haven't really plotted per se, but he is on the guard and will be running himself absolutely ragged on no sleep and constant fighting/protecting until it eventually gets the better of him and he is killed by the Null. He will be revived with a few pieces missing (I haven't decided on the full ramifications yet, likely a few fingers, potentially an eye, and perhaps a little altered mental status but still waffling), so fun times all around!