This plot has been claimed by GabriellaGonzalez303 (tagged in the comments)

Title: A Stitch in Time
*Original or fanfic? Fanfic
*Fandom: Harry Potter [starts in Golden Trio era, mostly set in Tom Riddle's era]
Main character: Cassia Roland [name and gender can change]

Description: Cassia Roland had never liked her life. Being in the same year at Hogwarts as Harry Potter was just stressful, and her relationship with her parents was virtually nonexistent. So, when the opportunity arose for her to leave school early and go to work in the Department of Mysteries, she took it without looking back.

While travelling to the past was dangerous, and keeping things more or less the same was complex, Cassia soon found the time travelling to be great fun. After all, what other job was there that you could "accidentally" punch Salazar Slytherin in the face, then have a cup of tea with Merlin?

Soon, though, she's given a task that's far too much for her:

Stop Tom Riddle.

After some huge mistakes on her part, Cassia finds that not only has she erased her existence in the future, but she only has twenty days [number can change] to untangle herself from the web of stories and lies she's spun, if she doesn't want to cease to exist altogether. And how's she going to do that? With more stories and lies, of course. And snacks. Lots of snacks.

Plot points:

*• This is not a love story!!! Tom Riddle's whole Thing™ is that he can't feel love for anyone or anything. Cassia knows this, and therefore doesn't even try to go down the "maybe I can make him fall in love with me to get him to rethink things" route

• I was going to ease into the whole time travel thing pretty slowly — perhaps have 5 or so chapters with Cassia's everyday life before she gets the job offer

*• After she accepts the job, she doesn't immediately go into the "stop Tom Riddle" mission. There should be a few shorter, easier missions that take up about 1-5 chapters each before you get into the main story, so the reader can learn more about Cassia, how the time travel works, etc

• I was thinking that Cassia would be a Slytherin, because a) she's gonna have to be pretty cunning and stuff to not screw up the missions she goes on, and b) it just makes it easier if she can be in the common room and sharing lessons with Tom

• Cassia could possibly join the earliest form of the Death Eaters??

• I was going to have it so that rather than getting darker and darker (as it generally would in a book like this), things would just get more and more ridiculous and funny as Cassia screwed up the timeline more and more, until suddenly there's this realisation of "oh Merlin I've gotta fix this or I'm literally going to die" and everything just gets plunged into darkness

Other info:

• It would probably work best if Cassia's 15 or 16

• I don't have any other writing for this

• I don't have a cover or anything

• Heads up that the title is the same as a BBC show, so you might want to change it to something more original??