Gray-eye is the code name of one of the few once chosen to join the brotherhood of the groundskeepers, a secret order who's job is to protect the world from long forgoten creatures of magic and disturbances from other worlds, and once they find them, the task is simple, exterminate the threat.
But one night on patrol, Gray-eye stumbles upon a little gray wall-eyed cartoon pony, who looks just as surprised and scared as he is. The pony speaks to him with a sweet but scared voice and says "Please don't hurt me... I don't know what I did but I'm sorry."
The innocent voice rips in his heart and compels him to question the words and methods of his fellow groundskeepers, and gives him the tough decision to either let her live and risk for the world to take damage, or kill the pony and live with the memory of it's begging strabismus eyes looking into his.

"I'm Derpy. What's your name?"