No matter how cold-hearted you are, it's tough not to feel sympathy for a waif — a neglected or orphaned child.
From Oliver Twist to Harry Potter, literature is filled with stories of young waifs who persevere through hardship. In contrast to street urchins or ragamuffins, waifs are generally seen as wholly innocent victims of their situation. This fact may explain why waifs make such compelling literary protagonists. Who's going to root against a kind-hearted orphan? And who would admit it if they did?