Rejected by A Fake, Worshipped by Three Queens

There is a dragon in this world, and there is a Pantheon of gods with a High Priest at its head. Eighteen years ago an eight-year-old boy named Theodore put himself between the dragon's fire and three girls he cared for, and was lost in the flames. Those three girls are now a queen, a governor and a bard known everywhere. They went after the dragon together to avenge him, and in the course of it learned that Theodore did not die. He is living under another name, with five years of his memory gone, as a drudge in a tavern where his fiancée works him for everything she can get out of him. At the Harvest Festival ceremony she breaks off the engagement in front of the crowd, humiliates him, and raises a sword to take his life. As the blade comes down, the three women break through the door and drop to one knee to welcome him back. A divine artifact answers him and the power in him starts to wake. He is the High Priest of the Pantheon, and he still has no memory of the five missing years.