Being raised to save the world is a terrible upbringing. Being raised to kill a failed experiment is worse. Flame was one of the few false dragonets, being picked to replace Glory of the Dragonets of  Destiny. If he were to succeed, Flame would have become a figurehead, acting on the NightWings' word.

Unfortunately, their failure ended with him being scarred in one eye, an event Flame shows unbridled rage towards, with some saying his face is in a constant state of anger.
He's doing better now.