Luna's Adventure: The Overlord Windows game

Legend has it that every hundred years, a demon so powerful that he is known as the overlord descends into our world in search of a wife to kidnap in exchange for sparing humanity for another century. Lunafreya is a fifteen-year-old teenager who spent her day to day in her hard life as a peasant with her best friend Meya and her grandfather, in the Condemned World. But, when the time comes for the legend to come true once again, the overlord appears, and destiny wants Meya to be his victim this time. Everyone agrees with this. Except one person. Unable to bear living in a world without the person who is everything to her, the light that illuminated the darkness of her heart at the most gloomy moment of her life, Luna makes a decision: defeat the overlord and rescue her best friend costs whatever it takes. A final boss accessible from the beginning. Quite an adventure until you manage to defeat him.