(LOL this is basically a summary of the entire comic.)
Sparky was born in Coastline in 2017 to Amber and Jackal. Because of her superstrength, Jackal made her work on the construction site with him. She learned to swear from his colleagues.
When she was 4, Jackal died in a workplace accident. And then, when she was 7 (almost 8), she was taken to Hillslope. She thought it was because her mom couldn't afford to take care of her anymore. (Actually, it's because Peacock's parents didn't want her.)
In Hillslope, she was dragged into solving two mysteries -- Amulet's murder and Starry's assault. She ended up digging up Starcorp's meth lab inside Hillslope.
Meanwhile, she learned and mastered some sort of wild martial arts from Dragonfly.
In 2030, when she was 13, Peacock came and took her back to Coastline, revealing that he was her stepfather, and that he put her in Hillslope because his parents disapproved of him raising a kid that wasn't biological. But now his parents returned to the countryside, so he took her back to live with her new family -- Amber, Peacock, her younger half-sister Willow, and her older step-sister Fantasy who is attending college in Flower City.
After getting back to Coastline, Sparky started attending Coastline Middle School as a seventh grader. There, she met some good friends, Qibli, Sky, and Firecrackers. They would solve some mysteries together, and as they did so, they came closer and closer to a conspiracy at the heart of Starcorp.
There was a pickpocket at school. Sparky and her friends investigated. So did Myriad.
While exploring an abandoned apartment building, Sparky and her friends found a nuke. The MSS got involved.
On the New Year's Eve of 2032, Peacock's parents came to Coastline for a new year surprise. They were not happy at the sight of Sparky. They yelled at her and tried to chase her out. Peacock pulled Sparky aside and gave her a credit card, an address, and a key, and told her to spend the new year at that place -- alone -- until his parents left.
Sparky, being Sparky, called her friends and did some urban camping.
But apparently there was a miscommunication and some Starcorp goons came over to pick up the drugs stashed in the apartment because they didn't receive Peacock's orders to stay away. They freaked out at the kids and beat the crap out of the other three as Sparky was out buying food. Sky flew some of his poker cards down to alert her. She returned just in time and beat the crap out of the goons.
The rest of the new year passed rather uneventfully. They celebrated Qibli's birthday in the apartment. Peacock's parents left and he told them to get back to their respective parents. Before returning the key to him, Sparky made a copy.
To apologize, but mostly to shut them up, Peacock invited the kids over for Yuanxiao. That was when Qibli noticed something wrong with Fantasy's pearl necklace.
Sparky got called over to Qibli's place one weekend shortly after. Qibli explained to her how she thought the pearl was weird, and that she had made a map with her magic intuition showing where it came from.