Over the last decade, transgender coming-of-age narratives have, somewhat confoundingly, gone from unfamiliar to borderline cliché. There are dozens of books, shows and movies on the topic, including memoirs such as Janet Mock’s “Redefining Realness” and novels like Torrey Peters’s “Detransition, Baby.” The arc is familiar — from dysphoria to street violence to, almost inevitably, the recognition that one is one’s own finest work of art. Reading Alana S. Portero’s first novel, “Bad Habit,” set in the author’s native Spain and translated from Spanish by Mara Faye Lethem, I registered a “here we go again” feeling as its 1980s, working-class protagonist — whose memories begin at 5 and who is prepubescent for much of the story — enacts the now-familiar rituals of growing up trans. Fortunately, however, Portero writes with such a fine sensitivity to the balance of politics and poetry, community and childhood, that “Bad Habit” proves itself instead to be an exemplary and fresh example of the trans bildungsroman.