Xia Qianshi is the guardian of the earth who crosses into a parallel world inexplicably. It is a pity that this earth is not flat, and n parallel planes surround it like satellites, and they will collide with each other. Once in contact with other planes, The erosion rate of the earth will increase. Once the erosion rate reaches 100%, both Xia Qianshi and the earth will suffer. Therefore, in order to protect the earth, all human beings, and his peaceful daily life, he resolutely embarks on these famous It is the parallel plane of "Sword Art Online" and "re:0".