Del Seymour, a former homeless addict known as the “mayor of the Tenderloin,” and his biographer, Alison Owings, offer a raw, street-level view of San Francisco’s most notorious neighborhood. Seymour, the subject of Owings’ book, “Mayor of the Tenderloin,” pulls no punches, exposing the paradoxical allure of homelessness and the failings of well-meaning nonprofits. His insights challenge conventional wisdom about addiction and urban poverty, while his Tenderloin walking tours and Code Tenderloin jobs programs demonstrate his enduring hope.