Crowley is a Thirteenth Progenitor among vampires and a member of Seventh Progenitor Ferid Bathory's faction. However, he hides his strength under Ferid's orders and is actually equal in strength to a Seventh Progenitor.
Crowley is calm and brave which makes him a patient vampire who enjoys fighting any opponent. Even when he is in a tight spot, he remains calm with a pleasant smile.

Despite sticking to Ferid, he appears to be emotionally detached from him, such as throwing the latter out of the bus as "revenge". Crowley also appears to be quite unimpressed with Ferid half of the time, calling his antics "stupid" and even sympathizing for the children getting dragged into the mess that Ferid created. He also doesn't appear to trust Ferid and is not afraid to be blunt to him for it.