Definitely your super expressive style! I really like how all the characters have very "intense" facial expressions perhaps thanks to their large eyes, as they all look distinctively different from each other & your style in general is very unique and really easy to recognize! Also, perhaps because of the first characters of yours I interacted with, I have really learned to associate vampires as your trademark, even though you really seem to have 6 of them out of a big cast of characters.
In addition, whimsical and unique character descriptions! They all seem so exciting and interesting and you have such a great way of also presenting them almost like they were a cast in a cartoon show!