Two partners Effera and Jiliora escape from a slave boat with the aid of their friend Orlin and a young boy named Kilian. When Kilian is killed in the escape Effera and Jiliora take it upon themselves to return Kilian's pendant to his two siblings who are being held captive by Baron Celdion, who is plotting to take over all of the neighboring countries.

高中生水原诚因为设计了一个实验而被带进了一个叫欧巴查顿的异世界，认识了正备受由昆虫领导的白古龙国(Bagurom)威胁的洛斯坦尼亚王国(Roshtaria)的君主——露宜公主。同时被带到异世界的还有他的老师藤泽真理和朋友阵内克彦、阵内菜菜美两兄妹。为了找寻回到原来世界的方法，水原诚等人走访了三位大神官——水神官美津、风神官艾菲娜和火神官些娜，希望他们能协助他们返回原来的世界，但最终亦无功而还。在这个时候，水原诚和露宜公主的关系亦渐渐进展中；同一时间，由阵内克彦领军的白古龙兵则策划著如何占领欧巴查顿这片大地……