Sareki Oukoku

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A kingdom in the middle of the desert is the last city of humans that were against the Sand People. However, their next king, Kirameki, didn't want to fulfil the throne. The Sand People took the chance to kidnap the prince and replace him with an imposter, Kirameki's half-brother, Saga, who is a half human and half Sand Person. Kirameki was made to do hard labour then. However, he came back on the day of the Water Festival to get back his kingdom with Serafita (Water Goddess)'s help.