The fly island could be a place of wonder and magic, with sparkling towers and buildings made of shimmering crystal or other fantastical materials. It could be a hub of trade and commerce, with merchants and traders from all over the fantasy world coming to sell their wares. The island could also be home to powerful magical beings or serve as a sanctuary for those seeking refuge from the dangers of the world below.

Overall, a fantasy city with a fly island would be a vibrant and exciting place, full of endless possibilities and adventures waiting to be had.