The Witch's Servant and The Demon Lords Horns

Chapter 60: The Witch's Servant and the Great Witch
Chapter 59: The Witch's Servant and the Hunter's Spirit
Chapter 61: The Witch's Servant and the Little Master (1)
Chapter 59: The Witch's Servant and the Hunter's Spirit
Chapter 61: The Witch's Servant and the Little Master (1)
The Eternal Vivian is dying from an unknown disease and must rely on her young apprentice Betty and her servant Arsenio to make the cure. Unfortunately, one of the ingredients is Horn of the Demon King- something completely out of reach of the two. Luckily, on the first expedition to the Demon King's Castle they meet a girl(?) who may be able to help them out…
Related Series