Misty's Payback Time! (Patreon)

After hearing a voice talk to her telepathically, Misty kept obeying Jessie somewhat willingly, as the voice told her to. One day, she finally had a few moments to herself as Jessie left to destroy a town where trainers were trying to train enough powerful pokémon to fight her. The voice told her it was time for Jessie to be stopped, and Misty followed it to a lab where she found a vial. "Drink it", the voice said. And she did.

Power. The feeling of sheer, unbelievable power filled her as her body grew. Muscles that dwarfed even Jessie's, breasts larger than any she had ever seen, and the feeling. Misty could actually feel as if the world trembled before her growing physique. As she flexed, her already immense biceps grew larger, way above her head, and she definetely felt the ground shake beneath her feet.

She knew, right then. She was stronger. She was the STRONGEST. "Time for some payback, Jessie."

Miles away, Jessie finished throwing Cerulean City into space and felt the ground shake. Even though she was strong enough to lift an entire nation, what she hadn't felt in weeks crept up into her, even though she didn't understand why: Fear.