Ah, very good question. But...(what character were you thinking of getting rid of? Better not be a canon...)
Anyway...Here's the answer. This isn't by me. It's by Joneleth Irenicus.
"Well if you can write your character out of the story then I think you should be able to delete them."
So be sure to write a little ending story for that character so we know what happens to that person. Does that work for ya? ^w^