I fell in love with this pairing on sight about a week ago, after watching a fan vid on YouTube. If I ever read the books, it was decades ago when I was a child; I haven't watched either of the films Caspian appears in, either, although I intend to when I get my hands on them.
Have some fic (although only a drabble, at this point) as an introduction of sorts:
Pairing: Caspian/Edmund (implied)
Timeline: Voyage of the Dawn Treader
Disclaimer: Characters you recognise belong to C. S. Lewis.
Notes: Film-verse casting; book-verse timeline
Summary: The difference between meaning and intent.
“I want you to know I think of you as my brother, Ed.”
Perhaps you do.
But when you’re stumbling over your words, Caspian, when you’ve spent weeks looking at me as if you want to eat me alive, when your reticence and tone and inability to look me in the eye as you say it lends credence to the idea that you mean something else entirely, then forgive me if I remain unconvinced.
You keep using that word “brother”, Caspian. I don't think it means what you think it means.
Or not what you want it to mean, anyway.