Sheila

Sheila (シーラ Shira) is the Demon Queen who personally wiped out half of humanity and subjugated all the monsters. After experiencing the loss of her beloved dragon at a young age, she decided to kill as many humans as she could so as to create a world for monsters and monsters only. Upon meeting the Hero, Sheila decided she would approach him so as to get close to him, and kill him when the opportunity came; however, she finds herself to have accidentally developed romantic feelings for Exa. And so, putting up the façade of a meek monster, Sheila joins him in his journey.