My town's full title or theme is 'city of the setting sun & rising moon.'
The sunset-themed side of town is like a bustling vibrant fairytale city, containing the town hall, gate, and Retail buildings, most of the villager homes, fairytale public works and streetlights lining its sun-mosaic paths, and a sunset-themed castle. The castle has a few rooms themed around the sun/sunset, but also rooms with functions you would associate with evening festivities in general: a ballroom, a theater, and a dining hall. The whole feel of this castle & side of town could be described as Dionysian: full of excess, indulgence, flair, maybe overdone.
The moonrise-themed side of town is much quiter, with just the moon-themed castle, a few villager homes, an inn a little off the beaten path, a witch's house in the woods, and the town tree located in a grassy clearing of star-shaped flowers. The paths are not quite as busy, but they're adorned with worn moon mosaic tiles and lined with white flowers that glow in the moonlight. The moon-themed castle is owned by the in-game-mayor, and has a few moon-themed rooms, as well as rooms with more quiet and practical purposes than the sun-castle's rooms: a chapel, a library, and a bathhouse.
I don't like to see the owner of the moon castle and sun castle as like moon and sun goddesses, necessarily, more like representatives of two political 'houses' or 'lines' of families that have waxed and waned in power and favor in the city over time, using the moon & sun as symbols for their respective houses and differing philosophies (the Dionysian vs. Apollonian idea).
Overall it's just something fun to have to give my fairytale-themed city a sense of history and purpose, and to guide the way I decorate... I have a lot of fun with it and like it a lot!!