HFY stands for “Humanity, Fuck Yeah!” I find it is best summed up by this tumblr post:

This is where I’ll be posting my stories in this genre. The first handful were originally posted on the subreddit /r/HFY, (which is where I will continue posting all future stories, I just wanted to put them here as well). Unfortunately, I don’t have the original posting dates for those, so the dates on those will be the day I uploaded it, not the day it was originally written. All future stories will have the correct days.

If you want to read more of this kind of thing, head on over to /r/HFY! There are lots of people there who write many different types of stories using this theme, and they’re all great.

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