Prince Brand is the son of King Vargas, the ruler of Miscellania. He lives with his father and sister Princess Astrid in the castle on the western side of the island. Female players must get him to agree to marry them during the Throne of Miscellania quest, although they don't get married immediately. He also features in the Royal Trouble quest. Like his sister, he is rather vain. Brand loves cake and thinks he is an amazing poet.
Prince Brand may very well be modeled on his namesake Prince Brand from the Chronicles of Amber series. In addition to the name, both of them share that vain prospect on life and hair colour.
By changing your gender to and from the gender you had during Throne of Miscelannia, you can go through the proposal dialogue again.