Descend of the Throne (Jupiter Ascending

Saturn and Mercery Wise are two ordinary kids; they live with their over-protective aunt in the busy Big Apple. But they aren't ordinary, their aunt has no idea of their sneaking out and fighting bandits and criminals after dark when she thinks they're asleep. They know how to fight, somehow they've always been inhumanly good warriors. Little do they know that these signs point out that they are the children of a Jupiter Jones and Caine Wise, who had to leave them and fight in order to protect them from the war between Tidus Abrasax and his sister Kalique.
Tidus wants the Earth and the rest of the galaxies for himself nod that Balem has been dead almost seventeen years.
Mercery and Saturn know nothing of their parents or any war, but one stay he night when they sneak off, they discover that these criminals are no humans.
After being abducted, they are taken to Tidus, where they meet Malek; Tidus' son.
Caine and Jupiter must find them and tell them the truth, before it is too late.