Leo is a boy who narrarates the first book, Stargirl. He falls in love with Stargirl in the first book. He isn't as strange as Stargirl, so he is concise of the people who shun him for hanging around Stargirl. He breaks up with her in the first book. However, the second book, Love, Stargirl, is Stargirl's 'longest letter in the world' that will be sent to him.