Lock, Shock, and Barrel back-story
One cold night in Halloween town, Lock, a small little trick-or-treater was walking the lonely streets. He had recently had his parents taken away from him, and he was seeking a new family. Upon his aimless searching, he met a beautiful little witch named Sock, which he had an instant connection with. "Are you looking for a family, too?" she asked of the sad looking boy. "Yes, my parents have disappeared…" Shock had paused, and began to whimper, "I'm scared."
Shock had joined Lock, and they walked onward, still searching for their parents, or a new family. They searched the alleys, and had only found spiders and stray cats, which hissed at them as they passed. Eventually, after looking behind numerous of head stones in the graveyard, they found yet another cowering little boy clinging to a ragged teddy bear. "Do you know where my mum and dad went?" He whispered. They shook their heads, and exchanged sympathetic looks.
"I know where your no good parents went!" A loud voice had exclaimed from the hill in the graveyard. They looked upon a shadowy figure, and they began to walk closer. "What happened?" desperation was sprawled across their tone. The shadowy figure burped loudly, for he had eaten their parents. "Well, you see? They left you three! They left a note, that left you under the care of, well, ME!" he cackled.
Oogie, a Halloween town outcast, was looking far and wide for minions to raise. Of course he couldn't refuse the chance to finish off the small little kid's parents. So he took the three, and taught them how to be the most mischievous, manipulating, devilish trio Halloween town had to offer. They would grow up to practically worship Oogie, and found that doing his bidding was the most fun in the world.