Action

Jace Morvan lived a simple life. He worked a night shift, kept to himself, and didn’t expect anything to change.
    He had no powers, no status, and nothing special about him.
    He believed he was just an average person in a world where a few rare individuals were born different.
    That changed after one night.
    The next morning, Jace noticed strange changes in his body.
    Later, the necklace he had worn since childhood activated. It spoke with an artificial voice and revealed the truth.
    Jace was not human.
    And he was from a extinct race of beings who could siphon energy.
    If only he knew he could do more than that.
    Harem, No Yuri, No NTR, Aliens, superheroes.
    It's Action book with smut, not the other way around.