When Harry loses Sirius, a power wells up in him and the more people he loses, the more he desperately tries to keep them close. He manages to save one Severus Snape in the end. But now, Harry is living a solitary life, learning how to control his new abilities when an old friend comes knocking on the door to ask him if he is willing to teach the students of Hogwarts. With little teaching under his belt, Harry and Severus must teach each other and their students. But what can two former rivals teach each other?