Humanity and demonkind have been on bad terms for millennia, resulting in the continent of Leunders being split in two. Although the situation has stabilized between the races, the fragile peace breaks when the new demon king launches a fierce all-out attack. With all of the non-demon nations falling to the violence in under a year, humanity's hope rests in a special squad, led by swordsman Kyle Leonard, that must assassinate the demon king in order to bring an end to the war. During the dangerous mission, Kyle ends up in a clash with the demon king that brings him to the brink of death. As Kyle realizes he has lost everything he wanted to protect, a mysterious gem transports him back in time before the conflict even started! Now with knowledge of future events and a strong desire to save his loved ones, Kyle sets out to become even stronger to prevent the extinction of humanity.

Since childhood, Kazuhiro Kitase has been able to dream of a different world. He can return to reality by falling asleep or dying, and he can pick up where he left off by sleeping again. For years, he has had many adventures alongside Mariabelle, a beautiful elf who works for the Sorcery Guild. On one of their escapades, they come across the lair of a dragon taking care of its eggs. They inadvertently wake the slumbering beast, who promptly reduces them to ashes. For Kazuhiro, it is merely a temporary setback, as he can simply go back. However, he is shocked to find Mariabelle herself safe and sound asleep next to him. Kazuhiro realizes that his dream world is an alternate reality altogether. In the meantime, he makes the most of this bizarre circumstance, introducing Mariabelle to the sights and wonders of Japan. Now, with their time together spanning two worlds, their real adventures have just begun!

The future of the universe rests on one young man, Kamui Shiro, who must destroy either the Dragons of Earth or the Dragons of Heaven - two opposing armies. He alone must decide whether humanity should be destroyed to create a purified universe, or whether it should be protected to preserve civilization. Two oracles, the sisters Hinoto and Kanoe foresee the coming of the Dragons and predict opposite outcomes. Each sister gathers strength and ammunition to insure her own vision for the future. However, neither sister realizes that there is one man who has an even greater power than the Dragons, and that ultimately he will determine the fate of the earth. Which sister will prevail and how does Kamui fit into their struggle? The answer to this question will forever affect humanity. (Source: Manga Entertainment)

The kingdom of Metallicana is under attack from the Four Lords of Havoc. This party of villains—ninja master Gara, deadly thunder empress Nei Arshes, cold and calculating Kall-Su, and enigmatic dark priest Abigail—will stop at nothing to get what they want, even if it leaves utter destruction in their wake. High Priest Geo is desperate to help save the kingdom and its people. He unleashes the mighty wizard Dark Schneider, a man who used to be an ally of the villains. Unfortunately, Dark Schneider has his own plans in mind. Will he stop the Four Lords of Havoc or join them in their conquest of the world?