It was highly likely that he would have missed it. But the light seeped through the window just so that it hit his head perfectly. That's when Dean saw it in the reflection of the bathroom mirror; a grey hair. Dean let out a wail and stuck his hands into his hair. Castiel burst into the bathroom, his eyes wide with concern.

"Dean, what's wrong?" Castiel exclaimed

"I found a grey hair," Dean whined

"Excuse me?" Cas said

"Cas, I just found a grey hair on my head," Dean repeated

"I don't understand the problem. You have a couple actually," Cas said

"What! Why didn't you tell me?" Dean yelled

"I didn't think you'd care," Cas said

"Of course I care!"

"Why?"

"Cas, do you know what grey hair means? It means that I'm old," Dean said. Castiel tilted his head slightly and gave Dean a curious look.

"Every human get's old Dean,"

"First it was the crow's feet and the back pains… now it's grey hair!" Dean said

"I don't think you look old Dean," Cas said

"Says the one who can't age. You will always be beautiful while I quickly shrivel up," Dean said

Cas sighed in walked over to Dean, taking Dean's hand in his.

"Dean, I think you're beautiful," he said

"Cas don't-"

"Just let me talk for one second. Dean, I don't care how old you are. I don't care if you have one grey hair or an entire head of them. That doesn't matter to me. The first time I saw you, it wasn't even your body. It was your soul and your soul was the brightest and purist one. It also helps that your soul is wrapped in a very handsome package," Cas said

"What's going to happen when I'm a saggy bag of bones?" Dean asked

"I will be in love with a handsome saggy bag of bones," Cas replied

Cas took Dean's hands and placed them around his neck and took his own hands and rested them on Dean's waist. Cas leaned in and placed a kiss to the spot bellow Dean's ear.

"Plus, I'm thousands of years older than you anyway," he whispered into Dean's ear. Cas continued to kiss Dean up and down his neck.

"I guess I have a thing for older men," Dean replied sarcastically

"Apparently so. Dean?"

"Yeah Cas?"

"You know what I love about you?" he asked

"My charm?" he asked

"Of course. I love your eyes. I love all 236 of your freckles. I love your smile. I love your body. So please stop worrying about getting old because I am going to love everything about you for the rest of our lives. You're a hunter, a brother, and my best friend and that all that matters. Okay?"

"Okay,"

Dean didn't always have the best way with words but he was pretty sure that Cas knew what he meant. Dean took Cas' face in his hands and gave him a long kiss.

"So, are you feeling too old to spend some time with me?" Cas asked

"What do you want to do?" Dean asked coyly.

"I would like to get you naked," Cas said. Sometimes Cas' bluntness caught Dean off guard but in this case he didn't mind.

"That can be arranged," Dean replied

"I love you Dean,"

"I love you too Cas,"

Dean laughed as Cas eagerly grabbed his hand, tugging him towards their bedroom.