Shino, Sousuke and Hamaji had to witness their village being set on fire, as a dangerous virus supposedly killed all the other inhabitants. The three narrowly escaped the flames and were found by a strange man and placed in the care of the Imperial Church. Five years later, the former last inhabitants of Ootsuka live in isolation under the roof of a church building to avoid detection. They have become closer and consider each other family, even though they are not related.