Kind of stupid, but I decided to make one final search through my huge bookmark list after posting and just came across the story. The bookmark was to a list, not the story itself, and I missed it in the first couple passes.

That Shape Had None by Henry Weikel. https://starlightconvenience.net/posts/that-shape-had-none/

Doesn't seem like I can remove my post at this point, but hey, at least I can recommend it to you.