Eykha

Eiha (エィハ) also known as the 'Bounded One', she is Ibuki's Guardian. A slave whose body has been linked to a monster by a rital performed during childhood. Being connected by a special vine like an umbilical cord, the two, both the slave and monster share their lifespan, thus allowing the Bound One to control powerful monsters, therefore turning them into a sort of human weapon, The monster she is bound to is Val.