Billy Batson,

If Billy and Angel are adults, here is another different idea, without villains as the focus and with more development.
"Between Lights and Secrets"
Fawcett City changed completely when night fell.
The offices closed, the streets filled with neon lights, and a few blocks from downtown, Club Euphoria opened its doors. It was a place known for its dance shows and live music. That's where Angel Mackenzie worked, a dancer who had spent years perfecting every choreography.
It wasn't a temporary job.
It was the place where she wanted to prove that she could make a living doing what she loved.
Billy Batson had known her since before she got that job.
They were one of those friendships that seemed impossible to break. They texted every day, argued over trivial things, and ended up laughing five minutes later.
However, since Angel started working at the club, they hardly ever coincided.
She worked at night.
Billy... disappeared every time the city needed Shazam.
One early morning, Angel finished her performance and went out to the back alley to get some air.
She found Billy sitting on the hood of his old truck, with a bag of fast food in his hands.
—You're late —she said.
—And you're coming out late?
—Tie.
Billy lifted the bag.
—I brought you fries.
She smiled.
—I forgive you.
From that night on, they started a routine.
After every show, Billy waited for her outside. Sometimes they talked for ten minutes. Other times they drove to a lookout point from where the entire illuminated city could be seen.
It was the only moment of the day when both of them could forget about everything.
Until one night, Billy didn't show up.
Angel waited ten minutes.
Then twenty.
After an hour, she left alone.
The next day, she received a message.
Sorry. An emergency came up.
She didn't respond.
She wasn't angry...
She was tired of there always being an "emergency."
When they saw each other again days later, Billy noticed that something had changed.
—Everything okay?