How Tiania came to be under the guardianship of Kthanid is unclear, but she has apparently lived her entire life within his care.
During the events of the novel, Tiania guides Titus Crow, who has become lost in time and space, to Elysia. During his stay there, the two fall in love and begin a relationship, while Tiania shows him the wonders of her world.
Accompanying Titus Crow and his companion Henri-Laurent de Marigny on a mission to investigate strange occurrences in the Earth's Dreamlands, Tiania is abducted by a Nightgaunt and held captive by a servant of the Cthulhu Mythos Deities known as the Keeper of the Cage. Despite this, she escapes with the aid of Crow and de Marigny, and the three rid the Dreamlands of the blight which plagues it.