Who is Sean O'Shawn from Without Feathers and what is their importance?

O'Shawn is a fictional Irish poet whose work is considered difficult to grasp. The sample of his work that the reader sees, a short poem, is so obscure and disconnected as to be ridiculous. In fact, the poem itself is a parody of poetry that uses obscure references and difficult to understand language. Allen's parody implies that O'Shawn's work isn't merely difficult but more probably absurd and meaningless. O'Shawn may be specifically a parody of James Joyce, who wrote the very difficult book Ulysses, but many examples exist of obscure poetry.