Dean had noticed Sam's weird behaviour that morning.
To an outsider, Sam's behaviour was perfectly normal. He woke up around nine, hair mused and sticking up. Got his coffee, sat down, opened the paper... and spilled his coffee all over the table.
"Shit!" he cursed, leaping up from the table as the steaming liquid began to drip off the table's edge.
"Good mornin' to you too." Dean chuckled, tossing Sam a roll of paper towels. He missed.
Once the mess was cleaned up, Dean pulled up a chair. His younger brother looked up at him. "Yes?"
Dean shrugged.
"Dean, I can see you want to talk."
"It's just..." Dean tried to sound sincere, but it was difficult, him being a demon and all. "You just seem like you've got somethin' on your mind."
"Well, I don't." he responded flatly, flipping to the opinions section.
Dean's eyes flicked black, staring right at his brother. Sam looked alarmed. "Dean! What are you doing?!"
The black faded into green and Dean's rigid shoulders relaxed. "Reading your mind."
"What?"
Dean smirked, knowing full well that one of the most convenient demons powers was that of mind reading. "I know you're still upset that I'm a demon, and it's affecting your work. When's the last time you had a case?"
"Uhh..." After considering it for a few seconds, he scoffed. "I've been busy."
"With what? Your crazy, psycho, demon-brother?"
"Well, yeah. I never know what you're gonna do. You could fly off the handle at any moment!"
Dean rolled his eyes. "That's not exactly true."
"It's true."
"Look. All I'm saying is that I'm fine. Completely fine. Because I also know you're worried. I actually..." He didn't want to say he liked being a demon, but that's exactly what he ended up saying. "I kind of like being a demon."
"Dean!" Sam's voice rose. "No you don't. We'll figure out something. Don't give up hope, okay?"
Dean leaned over and rubbed Sam's head, further messing up his hair. "I won't."