Love, Lust and other desires

Selene and Mark are cousins, they have lived together with his family since she was almost 16 after losing her parents in a plane crash.

They always got along and were affectionate with each other... but it was the type of affection that was wrong.

Desires that overtook their lives ever since their teenage years up to their young adult lives made them question their morale and feelings.

But not only those primal instincts become a struggle in their lives, as new obstacles come to face them and their feelings.

Are they so wrong for feeling the way they do?
Or does love exempt their relationship from the blood ties that naturally keep them apart?

PS: The first Chapter starts off with smut.
Beware. And for the sake of the story bare with me on that.