Top ten loners in fiction

Robert Williams's first novel, Luke and Jon, won a Betty Trask Award, was translated into six languages and called "a hugely impressive debut" in the Daily Telegraph. His second novel, How the Trouble Started, was shortlisted for the Portico Prize for Fiction. His latest novel is Into the Trees. One of his top ten loners in fiction, as shared at the Guardian:
Boo Radley in To Kill A Mockingbird