Refreshing and wry in equal measure, Happy Hour is an intoxicating novel of youth well spent. Isa Epley is all of twenty-one years old, and already wise enough to understand that the purpose of life is the pursuit of pleasure. After a sojourn across the pond, she arrives in New York City for a summer of adventure with her best friend, one newly blond Gala Novak. They have little money, but that’s…