A writefag is a member of that small minority of posters who actually possess writing talent and, better yet, use it to produce and post relevant stories. /tg/ has an a small population of active named writefags. But with the drawback of a larger base of ANON writefags. Several of the named ones put out good stories, but are often swamped and bugged by /tg/'s constant request for fapfics. Most of the ANON writefags churn out utter crap that is hopefully fappable.
Writefags come in all styles, abilities and tastes, and usually stick to a certain theme regarding the stories they produce. This sometimes causes discontent as the overwhelming majority of writefags stick to Warhammer 40,000 material, leaving relatively few who write fics for other themes such as Dungeons & Dragons.
Threads where a writefag is posting are typically more active, especially as posters attempt to get the resident writefag to write one of their own sick ideas. Sometimes writefags will create threads specifically to take requests, which results in them getting swamped with requests.
Also sometimes fa/tg/uys come with an idea and try to find a writefag to make a story about it.
Just list their names here, linked to their story portfolio. Anything more like "this guy is a faggot" or "he wrote awesome story [blank]" will just start a third edit war.