One of the minor sadnesses of life is when you finish a work of fiction and then you miss a character from there, wishing for more interaction with that character (some examples in my own case: Gandalf, Twoflower, Lucy Pevensie, Sherlock Holmes, Pan Wolodyjowski, Elizabeth Bennet, JC Denton, Inspector Gently, and the Moomins). It's not so much that you want to meet that character in real life (my first thought was that I wanted to meet the character, but then I realized that I just wouldn't click with all of them). But you want something like eternal fictional life for the character (to be distinguished from fictional eternal life, which at least the characters created by authors who believe in eternal life are presumed to have even if this is not mentioned, just as they are presumed to have spleens even if this is not mentioned).
In heaven all tears are wiped away, and presumably this includes the minor ones. So how is the minor sadness of missing a fictional character met? One possibility is that all that is engaging about any person, real or fictional, is his or her way of participating in God. Thus the beatific vision of God will supply the reality that the character is a shadow of.
But although the beatific vision we hope to receive after death even before the resurrection of the body will give us a bliss fulfilling our deepest desires, there is something fitting to our nature to also receive back our bodies. Likewise, then, there is something fitting to our nature to also receive back contact with fictional characters.
Let's speculate. Does this mean that further episodes in their lives will continue to be fictionally created—either by their author or by oneself—ad infinitum? Maybe: these episodes might be set in an infinite afterlife, or they might would-have-been episodes in parallel universes. But there may be a way in which such extension could betray the finitude and integrity of the author's creation, even when in-story the character has eternal life (as Lucy Pevensie clearly does). Though this is definitely one option. Another option is that even the finite earthly life of any real person has infinite thickness, infinite depth of participation in God. If so, then one might enjoy interaction with the character by coming to a deeper and deeper appreciation of the character. Another option is that we might stick to the canonical works created on earth, but have the ability to re-enjoy these works even more deeply than the first time (say, by reaching back in memory to them).
An even more daring option is that we might be living in a very large multiverse and we might meet the real people of whom the characters were shadows. But I am not sure that this is what we really want--I think in at least some of the cases (JC Denton?) we want more of the fictional interaction, rather than a meeting with a real-life person like the character.
There are interesting parallels between this set of issues and the issue of losing a pet.
I suppose the one thing we can with confidence about questions like is that way in which our tears--minor in this case, major in other cases--will be wiped away will be surprising...