I got the idea from of the crowd-recommended superheroes in the song Superhero by Stephen Lynch (the Live at El Rey version). Fellatio Girl seemed like a hero that wouldn't work in any kind of feasible superhero story, but in a smut story, she works great.
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"On the floor!" shouted The Jizzler as he aimed his gun at random bystanders. The citizens all dropped to the ground, covering their heads, as he made his way to the bank counter. "Fill this bag!" he screamed at the teller, pointing his gun right at her.
"Alright, alright!" she yelled in terror as she frantically threw bundled 20s into the bag, not wishing to get shot.
The Jizzler turned around, making sure everyone was on the ground as the teller whimpered. Finally he turned to see the bag overflowing with 20s. He pushed them in and struggled to zip up the bag. When he finally got it, he snickered, aiming his gun straight at the teller.
"No, please! Don't!" she cried, but it was in vain. She fell back, her face, hair, and torso blasted with a torrent of thick semen. She lay on the ground, crying.
The Jizzler ran out of the bank cackling, shooting a couple more people on his way out. He slid into his car and floored it.
Heather Conlon walked down the street from school, a bag slung across her shoulder. A 20 year-old student, she had lush, shining brown hair falling freely, enticing blue eyes, and a beautiful form. A loose skirt, falling just short of her knees, fluttered lightly, flying around her long, lean thighs and toned, juicy ass. Her tank top granted her full, round bosom no modesty.
As she turned a corner, a white car swerved by. People screamed as the driver shot at passersby, hitting them in the face and chest with sperm.
"The Jizzler!" she shouted as she ducked. Looking around, she made a mad dash for an alley, disappearing.
In her place came a girl looking much liker her. In fact, it was her; she just wore a skintight red spandex outfit and a mask that covered the area around her eyes. She wasn't Heather anymore; she was Fellatio Girl. She jumped onto a building, spotting the car and following it along the buildings.
"C.O.C.K." she said into her watch, "Bring up the info on The Jizzler.
"The Jizzler," said a robotic voice on speaker, "Five serious convictions and four escapes. Cock is seven inches. After radiation exposure, his body became capable of producing semen more than ten times faster and thicker than the average man."