He's done it to me in CSI, to custardpringle in Buffy, to chopchica in SG:A and from the comments on mckay_sheppard he's also done it in Smallville and comics fandom.

He just seems a random troll. Anytime he wants a fic, usually for a rare pairing, he pings some random person and demands that they write it, insulting them if they don't. And pointing him towards existing fic with that pairing doesn't cut it.