I think it's hunenka's Just a Puppet on a Lonely String (http://archiveofourown.org/works/1321804/chapters/2750500).

Summary: Jensen was of royal blood, a successor to the throne. But then the Ackles kingdom fell and now he’s naked and in chains, standing on a stage to be auctioned off at the slave market, and Jared, the warrior responsible for Jensen’s fall, is very, very interested. (Written in response to a prompt at letskinkjensen on LJ.)

Thanks! You' re right. That's the fic I was looking for. I appreciate it.

Herminekurotowa is right, the specific fic you're looking for is my Just a Puppet on a Lonely String (http://archiveofourown.org/works/1321804/chapters/2750500).


To answer your second request, here are some J2/Wincest slavefics (all bottom Dean/Jensen, by the way):

The Light of Munin (http://archiveofourown.org/works/180210) by leonidaslion

Lot 607 (https://archiveofourown.org/series/24542) by tryfanstone

Long Hard Ride verse (http://zuben-fic.livejournal.com/46029.html) by zubeneschamali

Thanks, I'm off to reread your fic and read the other ones. I appreciate it.

Flightless Bird (http://foolsdance.livejournal.com/9291.html) by foolsdance: "Jensen receives an unwelcome inheritance in the form of a pretty young body slave named Jared. Unable to free him and unwilling to use the person in his care despite his attraction to him, Jensen is stuck between a rock and a hard place. Jared, meanwhile, doesn't know what to make of his confusing new owner, who has yet to punish him despite his many mistakes and doens't seem to want him in his bed."

Courtesan Series (http://archiveofourown.org/series/37107) by phantisma: "Jensen is a newly promoted courtesan in the House of Morgan, and this is his first night serving in the Great Hall. Jared is a gladiator, also in service to the House of Morgan. To honor Jared's victory over the champion of a rival house, he has been given the new courtesan for the evening."

Rattling Your Locks (http://infatuated-ink.livejournal.com/73226.html) by cherie_morte: "Born into slavery, Jared has been trained and used as a pleasure slave ever since he was a teenager. Rare and coveted because of his Alpha status, Jared has always sold to the richest and often cruelest of masters. His new master, the young but ruthless CEO of TradeMark Entertainment, Jensen Ackles, seems no different. At least, not until Jared stops to wonder what a consummate Alpha male like Ackles would want with another Alpha as his pleasure slave. Things only get more confusing when Jared arrives at his new master's home and finds that there are no other slaves. He soon learns that Ackles freed all of his father's slaves when he inherited them and has been a vocal supporter and patron of anti-slavery groups since. Jared doesn't know how to reconcile this knowledge with his master's outward coldness, but the more he learns about Ackles, the less he seems to fit into the assumptions that Jared has made about him."

Vidi, Vici, Veni (http://bertee.livejournal.com/70651.html) by bertee: "Jared is a famous, rough gladiator who's never been beaten. When Jensen arrives, scared, inexperienced, and now locked up with a bunch of sex-deprived gladiators, Jared has to decide how much protection he wants to offer."

Things We Can't Untie (http://magellanflies.livejournal.com/18225.html) by astrangerfate: "Jensen Ackles thinks he's prepared for his new job, training political prisoners as sex slaves for the wealthy elite. But when he meets his first client, a gorgeous, intriguing kid named Jared, his own doubts about his profession begin to catch up with him. Soon, he's developing a disconcerting attachment to Jared, and struggling with the full implications of his career."

Baiatul Pierdut (http://archiveofourown.org/works/454793) by minchout: "When the warrior king from the North decides to take Jared as his husband, Jared's world is upended. However, he quickly realizes that being captured by a handsome king is really the least of his problems."

Shelter in Place (http://foolsdance.livejournal.com/22487.html) by foolsdance: "When civilization crumbles and Jared has to flee the death trap that the cities have become, he heads for the refuge of his grandfathers cabin in the pristine Colorado mountains. He acticipates a long hard winter spent in solitude. What he doesn't expect is that the cabin would be already occupied, or who he would find there."

Prime Verse (http://archiveofourown.org/series/14309) by meus_venator: "In a cruel and capricious society where slavery is the norm, first born children or Primes become masters, all younger siblings become slaves or Secs at the age of sixteen. Second born son, Sam Winchester, has evaded his fate and helped others do the same while attending college and living as a Ghost, but his luck has just run out." (unrelated Sam/Dean)

The Child Corrupted (http://archiveofourown.org/works/523986) by lexicale: "Sam grew up in Master Azazel's house -- he doesn't know any different kind of world. When a hunter named Dean Winchester frees him, he doesn't even know that he's free. In his mind, he merely has a new master. Dean, of course, is oblivious." (Sam/Dean)

If you don't mind complete AUs, I really enjoyed The Winning Scenario (http://virtualpersonal.livejournal.com/241801.html) by virtualpersonal: "Disguised as a merchant during an information gathering mission on a gaming and pleasure station, Captain Dean hits the jackpot. Surprised to learn his winnings include a night with a pleasure slave, he is ready to reject the slave's services until he learns that the slave is human. There is no way he will leave one of his kind behind, no way. The pleasure slave, Sam, has his own secrets. Cylon torture and conditioning to make him a suitable commodity for the slave trade has left him with half memories, nightmares and psychological problems. If he knew Dean was a colonial warrior, there is no way he would leave with Dean and no way he would go anywhere near Dean's destination, the Battlestar Galactica." (unrelated Sam/Dean)

That's awesome! Really, I appreciate it. I have read a few of those, but most were new to me. I don't mind complete AUs at all. Thanks.

These are great recs-- maybe you'll find some more at the J2 recs slave tag (http://j2-recs.livejournal.com/tag/sex%20slaves).