Krul Tepes is the third progenitor among the vampires and the vampire queen of Japan. She is responsible for turning Mikaela Hyakuya into a vampire. Being a Vampire, she is far stronger than a Human and being a Founder among the vampires, she is capable of easily defeating other vampires.
Just like all other vampires (minus Mikaela), she views the humans as nothing more than livestock. She sees them as foul and endlessly greedy creatures who will do anything for their own personal gain. When Ferid Bathory slaughters the Hyakuya Sect orphans she carefully hid in Sanguinem and protected as livestock, she becomes enraged because he fatally wounded one of the seraph and allowed another to escape. She never mentions a word about the orphans and displays no interest in them. She saves Mika’s life against his will by turning him into a vampire, but this appears to have been done for her own personal interests. He refuses to drink human blood, so she gives her blood to him in exchange for making him dependent on her.
Even so, she is the only vampire who shows him kindness, and there are several moments when she hugs him or treats him gently. After developing a close bond with Mikaela Hyakuya, she shows concern for his family member, Yuichiro Hyakuya. She claims to like both Mika and Yu. However, it is uncertain if this is because she is close with Mika and is concerned for Mika’s sake or if this is because she wants to use the seraph for her own purposes. She also appears to trust Mika, and only she and Mika appear to know Krul’s true goals.