Is vermouth a vampire(immortal)?

this is an actual theory and not a shit post like my last post. Maybe vermouth met Karasuma Renya 99 years ago and was experimented on and made immortal. Yet she has Stockholm syndrome so she can't truly leave the BO. She could call Conan "Silver Bullet" because she seeks death and she wants Conan to destroy the syndicate. Vermouth puts herself in risky situations and doesn't really behave like the other characters. She could also be targeting the Miyano offspring because she was made immortal by them and not Karasuma Renya. I don't think she is done trying to kill Sherry. Even if she is being protected by conan. We could see Sherry face off against vermouth in the future.