Who does Theo find when he goes looking for Doug late at night? What does this person want to do?­

In Chapter 17, Theo thinks that the clues he and Doug have are a formula for an explosive. He slips out of his apartment in the middle of the night to tell Doug. Theo knocks on the wrong door; it's opened by Crow, who says, "I knew you would come. We must pray for deliverance, then you must go to your angel and take her away." She then slips a note into the pocket of his bathrobe.