In the fictional "Yun City", there are two "incompatible" colleges and universities - "Yunxi Academy of Fine Arts", which focuses on art, and "Fengqi Institute of Technology", which specializes in science and engineering. The two schools are only separated by a road, but they have been at each other's throats all year round because they compete for cafeteria windows, library seats, and sports championships. When students meet, they "make harsh remarks to each other." There is a legend that has been circulating for many years in Yuncheng: on the autumnal equinox every year, if two people with "unresolved knots" see the vision of "two moons in the same sky" at the same time, their souls will exchange, and the details of the legend will be temporarily forgotten.
