The Ripper appears to have killed Cynthia, Stephanie and tried to murder Mia because they did not stick to the secrecy code and told their real names. That would make some amount of sense, but it doesn't explain the previous murders.
The Red Lantern Guestbook
Why would a string of important and powerful men risk signing their names in a sex club's guestbook? Victoria even uses the list as blackmail material against Todd Browning...
