How to Kill the Demon King

The most ordinary, dreaming of a priest, one day, like a coincidence or a joke of fate, summoned the Demon King at the first summon, and the village became a mess. In order to prevent this, his grandfather, a former great priest, cursed and sealed the Demon King, and to manage this, he stayed with the Demon King, the starting point of the incident, 3 meters away and began to monitor him.
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