The thought that someone was able to create a new species of vampires was a big shock. However, with the technology advancement in the modern world, many tools and procedures may have been created and enhanced to make this possible.
Alex and Alicia knew about Princess Mira's case. Mira now couldn't be classed as a witch and she could not be classed as a vampire also. A witch with a vampire's heart was not something anyone had ever seen before. She was in between both of these species. She was an anomaly, something that was created for a purpose. But she was living proof that a new creature like her could be created. It was not an impossible thing anymore.
This revelation was very shocking, even for Alex. Even he never imagined that something like this could actually happen one day. Just who was this person who actually thought of this kind of madness?