Yui Komori was imprisoned by the Nimaki family, but as she grew increasingly depressed, she was briefly released back to human life. She met Mizushima Ichi, a girl born from a vampire and a human, and they became dependent on each other. Just when Yui was about to accept the pursuit of an ordinary farmer (not from YUMA), she was recaptured by the Ushimaki family. Later, she reluctantly married the six sons of the Ushimaki family and gave birth to a child...
So it's a story about NP+ and six little kids, it's not 1 VS 1, please don't read it like thunder. As for the original character Mizushima Ichi, she is definitely not the second female lead. She is really just a little girl who may become the bride of future generations.