My Contract With the Apothecary Monster, Volume 1 by Ayaka Sakuraze

After wandering into the land of Weem, Nea is offered the illustrious position of Songbearer, and forms a contract with Dino - a monster as beautiful as he is powerful. While Nea adjusts to her role (and Dino's peculiar brand of companionship) she is tasked with the search for the Grimmdoll Chain: an artifact in possession of the elusive Masked Monster.
Binding: Paperback / softback