The second season of Bye Bye, Earth. Adonis returns, empowered by darkness, as Belle awakens from her slumber — their fates bound by an inescapable destiny.

In 3015, the year of Huanli, two countries, Donatia and Kouran, are embroiled in a war of supremacy that is tearing the world around them apart. The small island Nil Kamui has suffered exceptionally from the war, with lands conquered in the name of each kingdom and stolen away from the people. To make matters worse, their deity, the Red Dragon, has gone mad, rampaging about Nil Kamui burning villages and killing people indiscriminately. Ibuki, a descendant of Nil Kamui's royal family, resides at an orphanage and refuses to take on the role of king. Abhorring conflict, Ibuki desires a peaceful resolution, however the chaotic world will not allow for such pacifism when it is being torn asunder by war. Despite his reluctance, Ibuki is drawn deep into this conflict. Can he rise to the occasion and save his country?

Despite having no real combat talent, kind 15-year-old Kurt Rockhans belongs to the famous party Flaming Dragon Fang. He is perfectly satisfied as the party's helper—until the other members kick him out and replace him with a stronger ally. Left without a way to provide for himself, Kurt begins searching for a job. With his job prospects limited by his lack of combat ability, Kurt gladly accepts any work that comes his way. During one such job, he meets Yulishia, an adventurer formerly employed by the royal family. Surprised by Kurt's impressive work, Yulishia discovers that he is no ordinary boy: Kurt possesses an astonishingly high aptitude in a variety of non-combat fields. Due to these talents, a court official tells Yulishia to offer Kurt a high status in the kingdom that would allow him to live in peace for the rest of his life. When Yulishia informs Kurt about his potential rank, he brushes off the offer, refusing to think of himself as above other people. Still unaware of his real power, Kurt continues taking as many odd jobs as possible, which might just make him a pivotal part of the kingdom before he even notices it.