These are so gosh darn adorable! I love how expressive each scene is. My favorites I think are Voldemort vs. Dumbledore (the death skulls vs the hearts of love is great!), Harry and the dragon (both expressions are priceless!) and, of course, the top one. The trail of letters is a really nice touch.
But that is a minor quibble. MINOR. I love how you draw Harry's hair, and his giant round glasses. I like Voldemort's look of glee in the last one, and how Bellatrix looks completely nuts. These are just so adorable!