The Lucian Bastard (First in the "Princess of Eos" series)

PLOT: 17 year old Princess Dusk Lucis Caelum and her valet, Somnus 'Sommer' Izuna (nickname said as Summer) are out of the city when they are found by Iris Amicitia and Libertus Ostium...with news that her father was dead and that the city had fallen...and the Nifflers never found the rumored 'secret entrance lab' said to run from under the palace to a tunnel behind Hammerhead. Libertus also tells her a message that Princess Luna had from her dad 'you know that thing you love more than anything? Have fun, don't let anyone get in your way, no matter what your brother and his friends say'. But he didn't realize what it meant until what she did as a response.
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NOTE: This is a story to go along the game, with nods to the movie and DLC...IF possible, that follows a different "Player" in the form of Noctis' young half sister, born from a ONS in Tenebrae. This does, for a short while of the actual gameplay part...which will appear longer in the story, portray "Underaged" as the OC is 17 years old, even though she had her father's permission to pursue this particular person. Her birthday in a blink and miss due to what they are actually doing at the time, but it will actually happen.