I love reading.  My favorites are fantasy novels.

When I was in middle school and first starting to grasp the idea that one could read for fun --gross right?-- I read an awesome series called The Dragonriders of Pern, by Anne McCaffrey.

Man, what an amazing series for a young reader (soon to be aspiring writer, thank you Anne McCaffrey) to cut their teeth on.
It is intelligently and imaginatively written, adventurous, suspenseful, emotional, and like duh, it's got people riding dragons!

Well anyway, in the very first book one of the main characters is being attacked by an extremely large beast called a watch weyr, a genetic cousin of dragons bred for guarding castles.

At the very last instant, as the beast is pouncing upon our hero, the watch weyr realizes its intended target is actually one of the very people it was bred to protect.

In a desperate attempt to fling itself aside and spare the life of our hero, the watch weyr snaps its own spine, killing itself.

Now, this is no dog, it's a descendant of dragons, intelligent, sentient, and centuries-old.  That killed itself to avoid hurting someone it didn't even know.  Without a second thought.

Sometimes, not always or even most of the time, mind you, but sometimes...

I wish I had never read that book.