Once upon a time there was a Duckman Drakeman, who was legally but not religiously (very, very few members of the waterfowl family Anatidae are actually religiously inclined. Many of them eat fish, for Jesus' sake!) married to a charming duck, who bore a strong resemblance to Claudia Schiffer, especially when she moved her head to let her hair flow hither and thither for the L'Oréal ad.
Clauduck was soon expecting. She didn't tell anyone, but she sure hoped to become The Duck with The Golden Eggs, so she ate gold dust and put the blame on pregnancy cravings. She soon stopped because gold doesn't taste good (if cravings you must have, might as well be caviar or crème de marrons Clément Faugier à la vanille1) and the dust made her sneeze. And anyway, it didn't work.
She soon gave birth to a litter of adorable little duckies and drakies, whom she all baptized Caesar because they were born by Caeserean section.
(What? Oh, yeah. Look, I did say very few of them, didn't I?)
All adorable? No. One of them… was not.
Yeah, it was a duckie drakie. He had the nose, ears, four legs and talons required for the job. But he was not… or was he? He didn't look good at all. And when he padded with its siblings after Clauduck on their pond, he did go 'quack', but that 'quack' sounded more like the hidden and sinful child of the Concorde taking off from Roissy-Charles de Gaulle airport, that time, yeah, but also all the other times put together, and the eerie song of blue whales from the North Pacific Gyre when they've been playing too long with plastic bags, with just a touch of the distress signal from Alien.
Clauduck had an extensive maternal instinct, and Drakeman loved his wife, so they kept their upper lip stiff and raised the strange drakie as they would their own, since, you know, he was their own: they'd asked for the video of the Caesarean section and the ob-gyn obliged, and lo', here it was, the fifth newborn extracted from its mother's belly, already subtly different and ear-splittingly cacophonous.
In the evenings, when all the babies were tucked away in their cradles and Caesar V finally quit making that ducking god(I did say very few, damn you, stop interrupting!)awful noise of his - on top of everything else he was a difficult child, severely allergic to his mother's milk and always developing bottom rashes like you wouldn't believe - Clauduck and Drakeman would hopefully discuss the hopeless situation. Only when Drakeman had had a trying day at the office2 did he occasionally accuse his wife of cheating on him with the postman, which only gave him another trying day at work with colleagues going 'What's the matter, Drake, your skip baby beat you up again?'. Clauduck and Drakeman would talk about the future of their offspring, or lack thereof, and sometimes ventured into mentioning that hopeful fairy tale, but they did agree that fairy tales were cryptic allegories meant to educate the masses and nowhere like a mirror of real life.
And Clauduck prayed. She prayed discreetly, but she prayed a lot.
And then it happened.
Caesar V's bar-mitzvah.
Was there milk in the cake?
Just because, you know, rite of passage into adulthood?
Miffed because his previous siblings' coming-of-age celebrations3 were too successful?
Apprehensive because his next siblings' coming-of-age celebrations4 would be?
Anyway. Caesar V cut the cake with a huge knife, giggled and roared.
The Moon zipped away, stabilizing 2 AU from Earth.
Justin Bieber stopped singing. Yeah, forever. It's an ill wind, huh?
Eta Carinae (not the author, the star) decided to wait no longer and blew.
Anak Krakatoa decided to do like Daddy.
The Northern Pacific Gyre thought it could do much better than The Old Faithful. It did.
The Pillars of Hercules got drunk, leaned on each other and collapsed. So much for beaches in Provence in the long term, ha ha, that'll teach them to raise the prices of everything at the start of every touristic season, assholes! And next time there is a Zanclean flood, bring out the cameras - YouTube is waiting!
Caesar V was momentarily nonplussed at seeing everyone around him dead with bleeding ears, but took it in stride. He carefully put down the knife (you should always be careful with those things), straightened up, grew to a size slightly inferior to that of the Mont Blanc5, bumped his head on the goddamn ceiling and settled for the size of Dolph Lundgren in his prime. While he was at it, he also settled for Dolph's looks at the same age - a wise choice.
Then he realized he was hungry but not in the mood for cake, so white shark - oh shit no, no sea. Okay. T-rex.
He remained a T-rex for a while, but when there was no longer anything to eat in the vicinity (those motherfuckers eat a lot), he thought about it. Plus, T-Rex extinct, so no mating: tough. He tried a few other glorious, powerful shapes for shits 'n giggles - that kept him busy, which was good, because boredom. But female Siberian tigers were quite far away, female white sharks were still in the goddamn sea and he'd always been afraid of waves and anyway without the moon at the proper place seas and oceans were in a mess, and as an African elephant he kept being hunted for his tusks by rare but extremely determined and well-equipped survivors, something he found mighty irritating. Plus, the hunters kept mentioning a 'foundation', and once one of them walked up to him saying 'Come on Son, change back and come home!", which, you must admit, was weird.
He was also a very beautiful and delicately scented Papa Meilland red rose for a while, but just sitting there and looking pretty, the boredom was excruciating.
Then, as a black panther (still no mate but aesthetically pleasing), he happened upon a duck pond. With ducks.
Why not, he thought.
Plenty of food. Plenty of mates. Plenty of ponds. Plenty of shapes to shift into if drakes got into a competitive mood.
Just to frighten his rivals away, you understand. Because, for all being a shapeshifting living nightmare, he was not and had never been a cannibal.
And, he solemnly swore on the spot before shifting6, he would never be.

Footnotes
1. Clément Faugier's vanilla-flavoured chestnut cream
2. http://www.scp-wiki.net/dr-bright-s-personnel-file
3. The parents were always careful to avoid sibling rivalry. They were nice that way. Caesar VI's is in two weeks, and Caesar VII's middle of next month. You're all invited.
4. See previous footnote
5. The mountain, not the pens
6. Don't you know? A Panthera pardus' oath is universally considered as much more reliable than an Aix galericulata's.