Kakushite Mahoutsukai Noi Garene wa 100-nengo, Hanayome to Natta

Noi Galeneé, the country's greatest magician, lives alone in the mountains on the outskirts of town. One day, she is ordered by the Crown Prince to watch over a boy possessed by the Demon King, whose reawakening has been foretold by prophecy. Noi names the boy Cardia and takes him on as her new apprentice; however, the day of the Demon King's awakening draws closer with each passing moment...