This is an upload of something that was posted on a different site. The original description is down below.
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A long overdue gift for roku/SKINMAN. This is based on one of his pictures: Big Dum Carchaser.
Nathan is a marathoner with an ego bigger than any race he's ever competed in. During one of his practice sessions though the park, something beyond his control decided that it's time for a change.
That's all there is to it. It's a simple story about a straightforward transformation. It also contains the theme of intelligence draining, so fair warning to those who don't like that sort of thing.
I'd like to thank roku/SKINMAN. This story may be a gift for him, but it's nice to finally get back to writing again. I hope to upload more soon and not once every few years.