Some other fics to add to your reading queue (with added sequel).

Hard Road by Aleisha Potter (http://www.fanfiction.net/u/1481621/Aleisha-Potter)
Dean discovers a few truths about himself when he and Cas are forced to go undercover on a hunt to the very last place Dean ever thought he'd find himself: a gay resort, called "Last Hope", geared towards failing homosexual relationships.
Rated: M - English - Drama/Angst - Chapters: 21 - Words: 61,080 - Reviews: 675 - Favs: 1,199 - Follows: 813 - Updated: 7-11-13 - Published: 5-2-11 - Dean W. Castiel - Complete
Links: http://www.fanfiction.net/s/6958847/1/Hard-Road | http://archiveofourown.org/works/194155

Long Journey by Aleisha Potter
Sequel to Hard Road. Sam and Dean work with Cas to find a way to reunite Gabriel's grace with a physical vessel while Sam learns more and more about the archangel. Bonds will be formed and Bonds will be tested.
Rated: M - English - Drama/Romance - Chapters: 1 - Words: 1,504 - Reviews: 10 - Favs: 41 - Follows: 70 - Published: 7-11-13 - Dean W. Castiel Sam W. Gabriel
Link: http://www.fanfiction.net/s/9481120/1/Long-Journey

For Richer or Poorer, or Maybe Just as Monster Bait by diamorem
Dean and Cas go on a hunt (with Sam assisting) where they have to pretend to be married to catch the monster. Exactly what it sounds like: a fake marriage fic featuring cooking, babysitting, drunken confessions, and one out-of-control game of Big Gay Chicken.
Link: http://archiveofourown.org/works/936451

The Proposal: Supernatural Style by SuperNaturalGurl32 (http://www.fanfiction.net/u/2782501)
This is a story based off the movie The Proposal. Where Castiel a pushy Boss forces Dean his assistant to Marry him so he doesn't get deported. Eventual Destiel!
Supernatural - Rated: M - English - Humor/Romance - Chapters: 14 - Words: 22,650 - Reviews: 83 - Favs: 68 - Follows: 57 - Updated: 8-30-11 - Published: 7-5-11 - Castiel · Dean W. - Complete
Link: http://www.fanfiction.net/s/7149988/1/The-Proposal-Supernatural-Style

The Profound Proposal by OhMyStilinski (http://www.fanfiction.net/u/4439440)
The Proposal!AU Pushy boss Dean Winchester forces his assistant Castiel Novak into a marital hoax to avoid deportation. While immigration agent Henriksen is set on capturing them, Sam tries to use his lawyer status to help clear up the situation, but ends up getting into a mess of his own. Destiel & Sabriel. Rated T for suggestive parts, it pretty much follows the movie plot.
Supernatural - Rated: T - English - Humor/Romance - Chapters: 6 - Words: 23,687 - Reviews: 33 - Favs: 32 - Follows: 70 - Updated: 8-15-13 - Published: 7-11-13 - Dean W. · Castiel
Link: http://www.fanfiction.net/s/9480569/1/The-Profound-Proposal