Tyff is Kelley's roommate. She is a parts model, so she models her hands, feet, legs and certain parts of her body. She uses very expensive bath products, so when Lucky spills one of these products into the tub of water, Kelley is concerned Tyff is going to kill her.
Tyff turns out to be a Fair Folk too. She was a lady-in-waiting for Queen Mabh. Tyff was banned from the Otherworld for a set period of time. During her sentence, Auberon decided to the close the gates between the Otherworld and the mortal world, trapping Tyff in the mortal world.