Board Thread:Lords of Shadow 2/@comment-24686422-20140330064950/@comment-9249716-20140402020236

Carmilla wouldn't become a vampire until she split her soul and her dark side became Lords of the Vampires. One could also speculate that the blood in the castle needed to feed on Dracula's negative emotions because as we've shown, the blood didn't really go crazy until Dracula became a vampire and he tried to regain his powers.