We don't have all the pieces of the puzzle and the writer, as is his wont, doesn't give away any spoilers. I bet Marvin will come after Penguin or after coffee with Kendra. My theory is that Anna leaves her house through the back door. She goes to Rob's cobra. She goes to meet Rob or comes back from him, she's furious and sad at him because he lied to Anna about David or tried to use her. And when she was leaving, Chris could have called or texted her and asked for pictures or a video of her asking Anna to record herself masturbating for him.