Not smut. (Destiel, Paramedic!Cas AU.)

Dean, well, as always, he seems to find him and his baby brother, Sammy, in sticky situations. Dean is a hunter. Cas, well, after he lost his grace, he found a new way to do what he's always wanted to do, help people. He became a paramedic. One of them kills, and the other saves, the most unlikely pair to ever come to be, right? Well, it doesn't happen how you might think, Dean keeps getting himself hurt. Cas keeps having to save him. Of course, Dean's little brother, Sammy? He keeps finding himself in the middle of terrible sexual tension between the two. Poor Sammy...