Fluttershy's voice explains
You see it all began a long long time ago. Back in the age of myths, before the fall of Tirek the first; there was a creature called the Moochick. He was an immortal being who guarded the rainbow of light. His duty was aided by his companion, Angela Bunny; a magical rabbit who was from a warren of intelligent and long lived rabbits. However though she is important, being the oldest traceable maternal line of Angel Bunny's family; she is not where my Angel gets his more unusual abilities from.
For you see a few years before Angela would meet the rabbit who would be her mate, he did not even exist in our world. There is no trace of him.
Discord interrupts," Wait are you telling me that Angel is descended from an extra dimensional creature."
Fluttershy responds, "Discord let me explain things, it will make sense in time."
"Alright fine" The god of chaos pouts.
As I was saying, a few years before Angela met him her mate did not exist. However there is a legend that tells of what he did after he came to this world.
They say he appeared in a flash of golden fiery light, bones and armor exploded around him. An echo of the words "Though Shalt Snuff It" boomed across the valley where he appeared. All accounts agree on one thing, this was no ordinary rabbit. For immediately after arriving in our world, this bunny ate of a magical bush that granted great wisdom and intelligence.
Most creatures would use this to better the world, but this was during the dark times of Tirek the firsts rule. For better or worse, this meant that shortly upon gaining intellect to reason and think; this ancestor was set upon by one of Tirek's fierce dark knights.
And though the knight was a demon more than ten feet tall, with swords and armor forged from dark magic and steel; it was no match for that bunny.
As it ran towards him the rabbit crouched, then sprang straight at him. It's jaws ripped out the knights throats as it gnawed it's in arms, gaining the powers in its demonic essence. As the dark knight of Tirek fell down quite dead, the rabbit decided that any who would dare to attack it shall be ended by its paws and jaws. Dragging the knight, who was ten feet tall, away to a nearby cave it set up its warren.
As time went on more and more dark knights came to slay the rabbit, and all fell to its might. It was a terror unlike the world had ever seen, and Tirek lost many knights to its unusually large and powerful teeth.
One day while it sat upon its warren of bones and armor within its cave, it saw a horrific sight. A lovely white lady rabbit was fleeing from a vicious and mad bat knight. The rabbit, now known as KB the Killer Bunny and Knight Slayer; instantly went into action.
Like a thousand angry fluffy fiends bound to one body it leaped from its perch and raced towards the bat knight. With a mighty bound KB soared through the air and in one bit took its head clean off. Upon spitting out the batty tendons, KB turned to the lovely white Angela before it and bowed.
For though it was a terrifying beastly bunny it was still noble at heart.
Angela Bunny, moved by its great heroics; fell for KB right there. When the Moochick found them they were very much in love. And for his resemblance to an ally of his old world who once fed him many knights, KB did not attack the immortal mage. Despite its terrifying actions and bloody reputation, the Moochick agreed to allow his little Angela to wed the Killer Bunny.
And they did make an arrangement that Moochick would direct as many of Tireks knights and demons to their warren as possible. So that KB might smite their foul evil from this world. It is said that without the actions of Killer Bunny, the original Firefly would have been overwhelmed at Midnight Castle even with the aid of Meghan and the Rainbow of Light.
And so as time went on, Angela and Killer Bunny had many babies. And one in particular took after both, but was more like his father in his desire to destroy evil with his paws and jaws.
And this continued on all the way up to me beloved Angel Bunny, who protects my cottage from danger and monsters alike.