Ruphas Mafahl, the black-winged overlord and leader of the Twelves Stars of Heaven, has been vanquished. A man wakes up in the body of the Exgate game character Ruphas, two hundred years after her defeat at the hands of the seven heroes. The game world of Exgate he knew is no longer ruled by humans—and it is no longer just a game. Exgate is a world of its own where the characters think, feel, and live just like he does. Ruphas journeys through Exgate, looking for the long-disbanded Twelve Stars of Heaven. Ruphas is without country, army, or allies. A question remains: what is the real reason an ordinary man was reincarnated into Exgate as Ruphas?

In the not-too-distant future, the human world has long been overpopulated. Humanity marched to the stars in search of a new home, and just as this was going on, the moon's alignment caused massive earthquakes to ripple across the world, lasting several decades. Humanity was demolished. When the land finally recovered, humanity reemerged to face this strange yet familiar world. Will we, who once lorded over this domain, still remain the masters of this world?

Being a girl of both spirit and human blood, eight-year-old Ellen has power over the elements—though not the traditional four-element kind. She has the power to transform her surroundings by manipulating the elements of the periodic table. On top of that, Ellen also has a great amount of scientific knowledge due to being a scientist in her past life. During the war against a neighboring kingdom, Rovel Vankreift, the hero of the Kingdom of Tenbahl and eldest son of house Vankreift—as well as Ellen's father—was fatally injured. However, the spirit who fought by Rovel's side, Lady Origin, brought him to her realm to save him from the clutches of death. Lady Origin, who happens to be the Queen of the Spirit Realm as well as Ellen's eventual mother, is one of the most powerful spirits in existence, making little Ellen quite powerful in contrast to her innocent looks. But even a family as happy as this one has its fair share of problems, as Ellen and her parents are forced to reconnect their old ties to the Vankreift household in order to defend their relatives' honor—all while hiding Ellen's dangerous existence from the public to preserve their undisturbed happiness.

"Classes" are given at the age of 10, and the presence or absence of "skills" greatly affects life. Arel, the son of "Sword Princess" Fara and "Magic King" Leon, has been branded as "Classless"... But even without a job or skills, Arel believes he can persevere through effort.