The light spirit Aska was captured by Thor a long before the game took place. However, the civilization had to contain him, paralyzed, because they lacked the technology to experiment on a spirit. Before they could develop this technology, the comet Samier crashed into Thor, plowing it miles into the ocean. Thousands of years later, the city surfaces thanks to the intervention of the player. The player now can go on an optional side-quest to free Aska.
In one of the end-game sidequests, a man named Grahan asks you to find a series of treasures his father, a pirate, once hid all over the world. You can keep most of them, but there's a special one you have to bring back to him. Turns out it's his mother's wedding dress and Klarth comments that Grahan's father knew what the important things in life really are. Likewise, the reward for clearing this sidequest isn't money or items - it's simply making Grahan happy.