Bouncy is a quote-unquote "Powerpuff Girl" in my fan fiction "Fill in the Blanks". I used quotations because she technically isn't a Powerpuff Girl. In fact, the original three don't even know she exists.
From my story so far, we can tell this much about her: she is basically as powerful as the three Powerpuff Girls combined. In fact, she was created when the powers of the three girls were drained from them and combined into pure energy. Mojo Jojo, her "father" of sorts, discovers that she does have a single strand of human DNA, and that strand is what allows her to have brain activity.
She is being held in a containment field at Mojo Jojo's hideout. She tries to escape and reunite with Buttercup, the only Powerpuff Girl to have maintained some superpowers.
She is powerful enough to blow up the world multiple times, and the main characters of the story believe that she will be used to blow up the city of Townsville.
(Phew, done with the background info!)
This is what she would look like if she was an actual Powerpuff. You can see three strands of her hair, one for each of her sisters. However, because Bunny, the "fourth Powerpuff", was the inspiration for her, I worked her signature color into Bouncy's design.