Who is Wormwood from The Screwtape Letters and what is their importance?

Wormwood is Screwtape's hapless young nephew, the person to whom all the letters are addressed. Although the reader does not encounter Wormwood directly, a lot about his character is shown through Screwtape's responses to him. He is a young devil, full of fun, laziness, and selfishness. He is irresponsible. One can just imagine him going off to have fun with the other young devils and leaving his important work undone, yet still having youthful optimism that everything will turn out his way.