During the early stages of their 'we're not dating, yet, but we're still going to flirt the hell out of each other' phase, Dean and Castiel had taken to pinching each other's backsides, during the most inopportune times.
The first time had been an honest accident. It was dark, in the building they were checking out, and Dean had reached out blindly. When he felt something solid, he squeezed it slightly.
Turns out, it had been Castiel's arse, and it had lead to the angel letting out a high-pitched squeak, a much higher pitch than his normal deep tone.
The blond had to burst out laughing at it - it was too funny a sound not to.
The second time was Cas getting payback. They were standing at the counter of some nameless fast-food restaurant, the hunter ordering dinner to take back to the motel, where his brother was residing, holed up doing research.
When the angel finally made his move, pinching the skin of his backside, Dean was hugely embarrassed to realise that he had let out a similar sound to the one that the blue-eyed man had let out. His cheeks flushed a shade of pink, making his freckles stand out slightly.
Castiel just chuckled, understanding Dean's laughing-fit not too long ago.
The third time, it was Dean's turn to do the tormenting.
They were standing around the library in the Bunker, getting ready to leave for a case. Sam was there, and when he heard the squeak the angle let out, he couldn't help but burst out laughing. Dean howled along, finding the red blush on Cas' pouting face too funny not to laugh at.
Fourth time - Cas' turn once again.
They were in a bar, while Dean was chatting up some girls, Sam and Cas already sat in a booth, the blond standing by the table, too busy talking to sit down. Or listen to the angel's calls.
So, in an attempt to both humiliate him, and get his attention, Cas gave his arse a pinch, and the elder Winchester jumped almost a foot in the air, the noise always one of the products of the game.
Dean was more than embarrassed, especially when one of the girls he was talking to asked if he was dating the trench-coat clad people/characters.
They were continuous in their war, until Charlie stayed in the Bunker. She caught sight of Dean's hand making it's way towards Castiel's backside, and decided to say something.
"If you guys need and excuse to touch each other's arses, just start fucking already. It'll be much better than whatever the fuck you guys are doing there." 'Blunt and to the point. The only way to get anything into their thick skulls.' She thinks, shaking her head.
She storms out the kitchen, making her way towards the library, grasping Sam's wrist to drag him with her.
The next time they see the elder Winchester and the angel, the both have sex hair, and they don't attempt to pinch each other's arses anymore. Instead, they grasp hands, smile fondly at each other, and stare into each other's eyes.
Charlie thinks this is much better. Sam isn't quite sure.