Vampire Game by Judal (amazon)

Vampire Game is an excellent manga that blends together humor, a fantasy setting, shojo angst, and a vampiric cat with an attitude problem. Princess Ishtar’s Great-Grandfather Phelios died while defeating the vampire king Duzell. Before Duzell died, he predicted that both he and Phelios would be reborn to fight again. Ishtar is totally self-involved, but she’s so forthright about being selfish that she manages to be charming. She also has a tendency to be very reckless about her own safety because her dependable and handsome bodyguard Darres always shows up to save her.
The vampire king Duzell has been reincarnated in the form of a cat-like creature, which Ishtar promptly adopts and lavishes with affection. Duzell can transform into a male version of Ishtar, which provides plenty of opportunities for gender-bending confusion. Ishtar’s habit of rushing into danger ensures that there is always a new adventure in Vampire Game. Darres and Ishtar are in love with each other, but difference in their rank and heritage keep them apart. The art is quite attractive, and the book is a light and entertaining read. If you’re looking for some fantasy shojo, check out this series.