Prompt: you're immortal i'm mortal and we kind of fell for each other but this is gonna get real complicated when i'm 80 and you're still a teenager because well i'm not sure how to say this but you do realize i'll age and die and you'll be left alone again right
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Dean and Castiel were sitting on the couch together, watching a movie. Castiel was snuggled up close to Dean, who was resting his chin on top of the angel's head.
"Cas.... have you ever thought about our future?" Dean asked softly, his eyes still on the tv screen.
"What do you mean?" Castiel said in response.
"Well, you're immortal. I'm not. What'll happen? I'll be like 80 and you'll still look like you're 17 or something."
Castiel sat up and turned to look at Dean, who met his blue eyes with his green ones. "Dean..... that is in a long time. A lot could change between now and then."
Dean took one of the angel's hands and looked at it, playing with it mindlessly. "I know, but still. What will happen, Cas? I don't know how I could live without you."
"We will be together for as long as we can, okay? So what if you will be 80 and I will only be 17?" Cas replied.
"Yeah, but other people might think it's creepy that an old guy is dating a teenage boy." Dean finally laced their fingers together.
"Technically I am the older one in our relationship. I am thousands of years old. You are only 18."
Dean chuckled. "Yeah, but to everyone else, I'm older." He paused, turning serious again. "What will happen when I die?" He asked quietly, eyes looking everywhere but at his boyfriend's face.
"Dean, we can be together up in heaven. Forever. Doesn't that sound nice?"
"It does." Dean admitted, letting a small smile slip onto his face. "Now, how about we get back to the movie? It's getting to the part where Marty McFly plays onstage at the dance. That's my favorite part."
