Kylie (Trinket) can only be obtained by using a Hyper-Dense Neural Chip on the tank containing Kylie Muir's disembodied brain in the Robotics sub-section of the Hydroplant.
Effect
While equipped, increases experience gain for skills by 10%.
Trivia
In 0.10.0, Kylie's effects were swapped with that of the Pet Rock (Trinket).
The description "You made her a promise, remember?" probably refers to the song "Promises" by Kylie Minogue from 2003.
There is a special interaction that occurs when talking to the Waterbot found in Power Services. While having the trinket equipped or in their inventory, Waterbot will point out to the player that they forgot to enable Kylie's speech function, her voice. It then greets Kylie, and Kylie speaks in her own voice to greet K18.
Once this interaction happens, Kylie will occasionally speak to the player while being equipped. She shows concern and offers encouragement while players are in combat, warns the player of the appearance of IS-0091 and she will bid players good night whenever they sleep.
As of 0.10.0, this does not influence the gameplay or story of the game.