QUESTION: Is it okay to kill a good guy character in a novel?
If a character needs to die for reasons of plot, sure kill him.
But remember that there are reader expectations according to the genre you write.
Readers of standard happily-ever-after romance are much less tolerant of death than readers of fantasy and science fiction.
SF/fantasy prides itself, in fact, on characters dying because dying is "real." That's why the editor in charge of the STAR WARS book franchise insisted that Chewie die some years back.
And, in romance, the only circumstances that allows the death of the hero or heroine is if one or both of them is a ghost or some other supernatural being so that death unites rather than separates.
Children, pets, and horses are also dangerous to kill in romance, and their death can mean the loss of a reader in other genres, as well.
I won't kill an established character without a solid reason to do so, and the character must die nobly to save others, or his death must bring about change so it has meaning.
In life and fiction, such an ending is much stronger emotionally. As one of my professors once said, "The primary difference between fiction and real life is that fiction must make sense."
QUESTIONS, I TAKE QUESTION;
If you have a writing question, contact me via this blog or at marilynn byerly at aol.com.