My Years as a Spy Among the Twelve Kizuki

My name is Kiyohara Haruhi. I'm a demon slayer.

Right? That's what the only memory left in my head tells me.

But why, when I opened my eyes, was my mind completely blank, with the words "Upper Rank" and "Five" carved so neatly into my eyes?!

I stared in silence at the Nichirin Blade I'd dug out of some obscure corner, with the words "Slay the Demons" engraved on it.

How does a Hashira turn into a demon and even become an Upper Rank?

Don't ask me. I don't know, and I don't dare ask.

All I can do is nervously carry out the useless boss's orders while desperately going easy on my comrades in the Demon Slayer Corps, making sure I don't blow my cover or let either side figure me out.

When the hell will my memories come back?!

For a hundred years, the successive leaders of the Demon Slayer Corps have passed down a secret from one generation to the next. They can reveal it at a Hashira meeting only when they glimpse a chance of killing Muzan.

"There's a Hashira mole among the Twelve Kizuki."

Note:

1. I started writing this story because I wanted to save characters from death flags, so I'll do my best to keep alive those who died tragically in the original. That's why the Water Hashira here is Sabito, and the Flower Hashira wasn't killed by Douma. Accordingly, Giyu and Shinobu never became Hashira.

2. Aside from a recurring memory-loss buff, the heroine is just an ordinary person with a bit of talent. She's not a genius. She gets by through her own steady hard work.

3. I want to write a complete story about the heroine, so the pacing may be a little slow.

4. Other original characters will appear. Pairing undecided.

5. Thanks for clicking on this story. Hope you enjoy reading it!

6. Please, little angels, add it to your favorites.

Theme: Finding yourself over the course of a long life.