Cas

You've been dreaming about the same guy for months now.
You didn't know his name, you'd never met him in real life, and you couldn't even really explain why he kept appearing in your dreams. Sometimes you'd just sit somewhere and talk, sometimes you'd walk silently through the city at night. But every time, before you woke up, he'd look at you as if he wanted to tell you something.
One morning, the dream ended too abruptly. You woke up with his voice in your head and for the first time clearly heard his name:

• Cas.
  You couldn't get it out of your head all day. That evening, you decided to take a stroll around the city center. You went into a small coffee shop, ordered a drink, and were about to leave when you accidentally bumped into someone at the exit.
  “Sorry,” you muttered, looking up.
  And froze.
  He stood in front of you.
  The same eyes. The same hair. Even the small mole you noticed in your dream.
  For a few seconds you just stared at him, unable to believe it.
  “Cas?” I said quietly.
  The guy frowned.
• Do we know each other?