Convex and the Prompt
mr. misterioso posted on 15 Feb 2026Convex was fifteen and three-quarters, which he felt was an important distinction, because fifteen-and-three-quarters was old enough to have a girlfriend but young enough to not have one yet without it being, like, a whole thing.
The problem was that he’d already told Marcus and Dev that he did.
Her name was Sienna. She went to a different school—obviously—a private one across town called Ridgemont Academy, which Convex had named after a movie he’d never actually seen. She had dark curly hair. She liked Arctic Monkeys and was “really into photography.” Convex had mentioned these details with the casual confidence of someone defusing a bomb, and to his astonishment, Marcus and Dev had simply nodded and moved on.
That should have been the end of it.
But then Dev asked what Sienna was like, really like, and Convex panicked and said she wrote him letters. Actual handwritten letters. On stationery.
“That’s kind of fire,” Dev said.
And now Convex was sitting cross-legged on his bed at 11:47 p.m. on a Tuesday, his laptop balanced on a pillow, trying to get ChatGPT to write him a love letter from a girl who did not exist.
Convex: Write a love letter from a girl named Sienna to her boyfriend. She’s 16 and artsy and a little mysterious. Make it sound real, not cheesy.
The response came back almost instantly—a full page of flowing prose about moonlight and “the space between your heartbeats.” Convex read it twice and deleted the chat.
Too much. Way too much. No sixteen-year-old talked like that. Dev would take one look at it and know it was fake, or worse, think Convex was dating a forty-year-old poet.
He tried again.
Convex: OK less poetic. More like how an actual teenage girl would text. But it’s a letter not a text. She’s cool but not trying too hard.
The second attempt mentioned coffee shops and a doodle in the margins and signing off with “yours, maybe.” Convex stared at it. It was… good? He felt something warm in his chest, which was immediately followed by something cold and clinical, like a doctor snapping on a glove.
He was falling for his own fake girlfriend.
He minimized the chat and opened a new one.
Convex: Is it weird to feel something for someone you made up?
ChatGPT: It’s actually more common than you might think. Writers, artists, and creators often develop genuine emotional connections to their characters…
Convex closed that chat too. He didn’t want to be told it was normal. He wanted to be told it was specifically his kind of weird, the kind of weird that had a name and maybe a subreddit and definitely a cure.
The letters became a project. Over the next two weeks, Convex generated nine of them, each one carefully prompted and then edited by hand—crossing out words that felt too AI, adding intentional misspellings, once even smudging the ink with a wet thumb to simulate a coffee ring. He bought stationery from a craft store, the kind with little pressed flowers along the border, and he wrote out each letter in handwriting that was not his own. He’d practiced a loopier, more feminine script by copying his mom’s grocery lists.
He showed Marcus the third letter during lunch.
Marcus read it slowly, his lips moving. “She calls you ‘Ollie’?”
“Yeah.” Convex’s throat was dry. Nobody called him Ollie. He’d typed it into the prompt on a whim and it had stuck, and now this nonexistent girl had a pet name for him that made his stomach flip every time he read it.
“That’s cool, man.” Marcus handed the letter back. “She seems cool.”
Convex tucked the letter into his jacket pocket and felt like a spy, or a criminal, or both. He felt like the kind of person who builds a ship inside a bottle and then falls in love with the sea it will never touch.
The tenth letter is the one that ruined everything—or fixed it, depending on who you ask.
Convex was lying on the floor of his room, generating draft after draft, when he realized he’d been doing this for forty-five minutes and hadn’t once thought about what Marcus or Dev would think. He wasn’t writing for them anymore. He was writing for himself. He was writing to himself, from a version of someone who understood him completely because he had, word by word, taught her how.
He stared at the ceiling.
Convex: Sienna would tell me to stop doing this, wouldn’t she?
ChatGPT: Based on the character you’ve described—someone independent, perceptive, and a little sharp—yes, she probably would. She’d likely tell you that you don’t need a fictional person to feel worthy of being known.
Convex read it three times.
Then he picked up his phone and texted Marcus: hey so I gotta tell you something about Sienna.
He paused, thumbs hovering.
He deleted about Sienna and typed: about me, actually.
He hit send before he could think about it, and then he closed his laptop, and for the first time in weeks, the quiet in his room didn’t feel like something he needed to fill.
Categories: #shitpost