Reincarnated into another world as a vampire's familiar bat, a girl evolves into a vampire after sucking the blood of a dying man.

This then leads to an even greater evolution, as she achieves the remarkable feat of becoming a high-ranking vampire.

Turning her life around from a lowly bat existence, the bat is bestowed with the name Merlil and obtains the status of a vampire princess.

Her vampire father then proclaimed:

「Merlil, you shall rule your own territory as a vampire!」

「No, I can't!」

Merlil, who used to tremble before monsters due to her frail mindset, completely changed her tune the moment she realized she had gained immense power by evolving into a high-ranking vampire, and began moving to acquire territory.

「Alright! I'll go acquire the biggest territory in the entire world!」

This is the grand invasion story of a reincarnated girl who, having risen from a feeble bat, comes to be known and feared as the Pure White Vampire Princess!

This work is also serialized on Kakuyomu.