noun. Just like a motherfucker, but with less mother, more step-brother, and less "ew."
Related terms: unclefucker.
Real citation: "I'm kind of in the "damp towels" camp on the Sayid-Shannon relationship. Sayid had more chemistry with Sawyer's glasses. I'm guessing Sayid-Shannon will be a healthy thing, ultimately. But Shannon damn well better have some issues — everyone else on the island does. "Skank" may be verboten, but I think she has behaved like a shallow, vapid, step-brother-fucker. She has some growing up to do. Whether they did it or not, I was glad to hear her say she wanted to go slow. And I'd really like to see her backstory now, to flesh out her character more.”
(xii, " 1-20: "Do No Harm" 2005.04.06," April 7, 2005, Television Without Pity, http://forums.televisionwithoutpity.com/index.php?showtopic=3125481&view=findpost&p=2754500)
Made-up citation: "As the Bible says, 'better a step-brother-fucker than a parakeet-jacker-offer.'"