Stars' Light - The Light Well Series

Jorian Tal has lived through every age of man, training great heroes and watching those he loved age and die, or worse, fall to darkness in countless wars. Disillusioned and out of faith in humanity, the last thing he needs is another student to train. Daughter of an ancient noble house, Sarannya Tatara's path is already decided, and yet she dreams of forbidden things: swords, dragons, and a life she can never have-until the day she holds one of the General's blades in her hand. As demons sweep over the land in a wave of darkness and corruption, Jorian has one last chance to right the wrongs of the past, and resurrect the ancient order of knights who once kept the world safe.
If he fails, all of humanity will be lost. If he succeeds, his long life can finally end. The empire he helped build centuries ago is on the brink of collapse, and everything rests on the shoulders of a girl who embodies the spirit of his greatest failure, a wound he still carries in his heart. For Jorian and Sarannya, history is repeating itself-and he has already failed her once before.