I'm less worried about this being a one-shot and more worried about its quality, actually. You have some egregious technical errors (such as your tendency to confuse "your" and "you're") and the length prevents you from getting a lot of character development. Also, you tend to use thoughts to repeat things in the narration. That said, the ending tied it off well.

This certainly has potenial. I love the idea you've come up with (Princess Peach dying under Bowser's hands), but the execution needs work. I'm considering taking up your offer and handing me the story. I'm a stickler for grammar and details, though, so if I do decide to do it, the first chapter will probably be rewritten. But know that I have my other 3 stories to work on (Breaking the Chains, Slaves and Soldiers, and Pokemon World Tour, check them out if you have time) and I have to deal with the pain known as 'Real Life', so you may not see it for a long while. But know that I'm thinking on it.

This seems so interesting!You should definetly continue this!

You shoud try making the chapters abit longer,unless there is a part that will make the chapter too long.