I recommend "Cassel's Little Monsters". This is a derivative doujinshi novel. It tells the story of Cassel's journey of slaying a dragon to redeem himself. At the same time, it will fix some of the flaws in the setting of Old Thief. It will make up for the regrets that Old Thief had created in the past. It is a very exciting novel. I hope you like this fairy's recommendation. Muah ~😗