The Prompt
Write a story in which a secondary character has a secret — they are having their period. This doesn’t affect the plot, but it does affect the way the secondary character behaves.

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Mary Robinette Kowal
Mary Robinette Kowal is the USA Today Bestselling author of a dozen novels, including Apprehension and the Lady Astronaut series. A winner of the Hugo, Nebula, and Locus awards, she is also a professional puppeteer and award-winning audiobook narrator. She co-hosts the Writing Excuses podcast, served as SFWA President, and has an asteroid named after her. Also, her cat talks.
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I wrote a very weird story based on this prompt that I bet I’m going to love when I take a look at it when the challenge is done. My brain loved trying to figure out how to make the secondary character’s period affect their behaviour but not the plot. I ended up writing about aliens trying to integrate into Earth culture, and about a woman tasked with buying flowers for her boss’s wife.
I’m so late finishing today’s story. I had a busy day with an oral storytelling event in the afternoon and then plans in the afternoon. I am determined that my story must be finished before I go to bed every single night, even if it’s after midnight. So, story number 17 is done! One of the characters in my story needs to make sure the group of men she works with don’t find out she is a woman, made more challenging by the fact that she just got her period. Bigger stakes I think than the prompt encouraged, but I couldn’t deny it once I landed there during the brainstorming session. Really great prompt. I admit I was reluctant to work with it. Julie, you convinced me to embrace the discomfort. Thank you for that. The discomfort is the bounty.
The story is DONE. It’s a crap draft, I could ratchet up the tension, but some new characters emerged and a sweet camaraderie unfolded and I went with it. I might work with these characters again, sometime.
Getting a late start on writing today. Super busy day. I have a few ideas but I’m not sure which route I’ll go down.
I’m super excited for the second half of Story A Day May. Happy writing.
On Planet A43, teenage girls are never moody. Except today, Nova’s best friend, Asi, is. That’s because Asi is having her period. She would be in serious trouble if anyone found out.
There is a reason behind why Asi is having her period and none of the other females on the planet are. For hundreds of years, peace regarding every aspect of life has been the foundation of A43. Why would this silly girl want to disrupt that by not following the rules.
Love it.
Intriguing!
I didn’t follow the prompt exactly. The secondary character’s behavior is affected, which affects her older sister, which affects the plot. It was kind of a sweet story, possibly too sweet, but at least there was conflict, and a resolution.
I really liked the prompt for being so concrete, and so much a part of everyone’s experience.
Walter, that’s a clever idea.
Genre: Personal Essay – first-person, discursive.
https://afstoryaday.blogspot.com/2026/05/asleep-at-wheel.html