When I first saw this topic my first thought was aromantic dean winchester. I know a lot of people already mentioned aro!dean, but here's my addition: I absolutely love the idea of dean, sam, and cas in a QPR. Before cas, it was just sam and dean; the two of them against the world. Sam could always tell when dean was having a bad day, and would make sure to sit a little bit closer, leave his hand on his shoulder a lil bit longer. And if at the end of the day sam rested his head on dean's shoulder, well he was just tired from a LONG day of researching at the library. Because dean needs those little touches, those little assurances. But it's not just dean. When sam has a particularly bad nightmare, dean will crawl into sam bed and wrap his arms around him and whisper "it's okay" and "I'm right here" like a mantra until sam eventually falls back to sleep. And then cas comes into the picture, and at first it's weird. It had always been just sam and dean, but now there was someone else in the picture. But in the end it worked it's self out one evening while they were "forcing" cas to marathon the Star Wars movies with them. Dean was sitting on the couch with sam on his right, half asleep with his head on dean's lap, and cas on his left, his right arm around dean's shoulder, and his left gently brushing through sam's hair. "This seems to have a calming effect on him, dean". Of course dean already already knew that, but the dorky smile on cas' face was worth it. The next morning when he woke up, with sam still passed out across his lap, and his head resting against cas' shoulder, he realized that this is all he needed. This was his normal. And he is going to do everything in his power to protect his little bit of normal- the two most important people in his life.
I'm sorry, I didn't mean for this to get so long. I just really love the idea of Team Free Will in a QPR