Stereo Hearts

Bailey (Last name) is the adopted sister of Mc (Last name) being part of the (Last name) family is tutor Mc gets away with everything while Bailey gets cut up and her blood is selled to the black market. When the brothers find out what Mc family is doing to Bailey they set out to the human world to save Bailey. While saving Bailey they find out that she is the future queen of Demon world. Making her the princess of the Demon world.

Lilith in this story isn't related to the brothers.