Dark Fang, a Changeling with Heterochromia iridum, causing his right eye to be green and his left to be purple, has lived with the Changelings his entire life. He always lived their ways of feeding off of love of other creatures. He has a mentor by the name of Waver he teaches Dark Fang and his best friend, Night Wing, all the ways of the Changelings. However, during the latest invasion, something traumatic has happened that made Dark Fang see the Changelings much differently. As they abducted a few fillies to convert to their side, it did not just help the Changelings, but it really hurt their former families as well.

Dark Fang, now displeased with the results of their way of life, has decided that maybe things can change for the better of not only the Changelings, but other species, such as ponies, as well. But when he tried to convince Queen Chrysalis not to attack Canterlot, things did not turn out into his favor as he was punished through banishment and had to leave Night Wing and Waver behind. As he traveled on his own, he soon finds an unusual pegasus who also seemed to have misfortunes that prevented her from returning to her true home. As Dark Fang has adventures with her, he soon learns that his purpose in life isn't always as what he thinks it is. He also learns that the mistakes he make in the past will one day come back to haunt him and that it will take a heavy toll.