The Dragon ("Cadmus")

The dragon is tasked with guarding the tower and its locked princess (who affectionately calls him Caddie), while also addressing the princess' needs. He is able to shapeshift into a more compact, human-form in order to serve and is highly skilled at cleaning, cooking, and containing chaos. His origins are unknown and his motivations are unclear.

• Is quite mysterious, and seems happy to remain mysterious. For example, he is tight-lipped as to how he learned all the skills needed to be a good servant, as it goes without saying that dragons usually do not learn such a thing.
• Has a hidden passion for teaching willing listeners, which Cecilia takes advantage of gladly.

• Cecilia: His ward, in a sense. In the beginning, Cecilia was quite frightened of the dragon on account of him being a dragon. However, after a couple of months of little aggression from the dragon, Cecilia grew bolder and started holding conversations with him. They grew closer after the dragon recommended some books from the tower's library, and formed a mini book club. The name Cadmus, which Cecilia gifted to the dragon, was actually the name of the protagonist from that first book exchange.
  
  Cadmus also taught Cecilia how to hone her meager, innate magic into something actually usable. They developed a mentor-student type relationship due to this, though it's quite rocky due to Cadmus finding it funny to press all of Cecilia's buttons.