This is an absolutely fantastic and awesome piece that is definitely getting put into my favourites.
The first thing I'd like to mention is that I love how you've kept the background minimal. The colour is a soft tone that doesn't overwhelm the rest of the artwork, but it still keeps with the colour scheme of the overall piece and the era.
Proportions are absolutely perfect, and your colouring is perfect for this piece too.
The touch of having the blood on the axe, multiple actions happening at once while keeping it simple and pale, realistic colouring for the vampires had the most impact on me. It made the piece feel complete and brilliant.