The title of Esther Yi's novel Y/N refers to an abbreviation for "your name" as it appears in a type of fan fiction where readers put themselves into a story. It's a way to inhabit another life, which is exactly what Yi's central character wants — but can never have. That tension drives the novel, as it explores loneliness, fandom, and K-Pop. Yi tells NPR's Ailsa Chang how it all fits together.