Wisty's Links
Initially she thinks of him as a pest to be disposed of as quickly as possible, but eventually she actually begins to care for him. Soon she starts ignoring her Vampiric duties to the Crown and starts focusing more on her future with Seiren.
As a fellow singer, Seiren had nothing but respect for Wisteria. He truly thought she was a rare talent, and a rare beauty, who deserved the spotlight. He aspired to be like her. One night when he discovers she is in fact a vampire, he seizes the opportunity to make her his. Despite seeing her kill others, he does not fear her.
She once loved him fiercely, but as the years rolled on she realized how little she knew of the world and decided to strike out on her own. She became quite wise, talented, and formidable, but still something called her back to Rothe. She decided to ignore it and pursue other interests, though her and Ashley still hang out she convinces herself its all just platonic.
Rothe is the one who convinced the King to turn Wisteria into a Vampire. He once loved her, but over the decades their relationship has become complicated. Regardless of her now being one of the most powerful Vampires, he still feels the need to protect Wisty as if she is still the meek mortal he once knew.