Flower-in-the-Night is a young princess of the Sultanates of Rashpuht who appears in the novel Castle in the Air. She is the daughter of the Sultan of Zanzib and eventually the wife of Abdullah and Ambassador to Ingary.
Flower-in-the-Night is said to be a very beautiful young lady, with large, dark eyes and long dark hair.
She is only allowed out of the palace at night, and even then only into the garden, as a prophecy made at her birth decreed that she would marry the first man she would see aside from her father. The Sultan wishes her to marry for political reasons to a prince from a neighbouring country.
She is first met when Abdullah falls asleep atop his magic carpet and is flown to her garden in his sleep. She mistakes him for a woman, assuming that all men look like her father (fat, bald and bearded). Abdullah is shocked by this, and promises to bring her as many portraits of men as he can, although he is uncertain whether he is in a dream or not. However he returns the next night with more than one hundred portraits, and Flower-in-the-Night says that he is better looking than them all. They declare that they love each other and decide they must fly away, to avoid angering her father. However whilst trying to determine how exactly the carpet works, Abdullah accidentally orders it back to his stall, and he is whisked away.
On the third night he returns, but whilst there a djinn, Hasruel, appears and kidnaps Flower-in-the-Night, flying off with her. Abdullah sets out to rescue her, thus providing the plot of the story.
She is not seen again until Abdullah reaches her place of captivity - a castle high above the clouds, which is actually Howl's castle, modified by Hasruel into a djinn palace. She and many other princesses are being held there by Dalzel, Hasruel's brother, another djinn, as his 'wives', although they are reject him, Flower-in-the-Night especially. As she is extremely intelligent, she irritates him by asking frequent questions which he cannot answer, and forces him to grant her requests in exchange for leaving him in peace, all the while planning to escape.
After Abdullah arrives to rescue her, she is initially distant toward him, causing him some distress, but when he asks her why she is acting so she tells him that Princess Beatrice of Strangia, another captive, has said that from his actions he does not love her. Abdullah convinces her this is not true, and they kiss.
Once they escape the castle, partly thanks to Flower-in-the-Night's intelligence, and all is put to rights, Flower-in-the-Night marries Abdullah and they are given the position of Ambassadors, and a house with a bluebell meadow garden in Folding Valley.