“SEX EDUCATION,” SEASON 2: THE DOCTOR IS IN

When it débuted on Netflix last year, the British series “Sex Education,” created and co-written by Laurie Nunn, established itself as one of the freshest, funniest, and most humane depictions of teen life in years. (Its second season came out on Friday.) It centers on Otis (Asa Butterfield), a mild-mannered teen who, despite being a virgin in a dorky windbreaker, in the first season becomes a sex therapist to his high-school peers. He’s got hangups—he won’t even masturbate—but, all around him, the world is bursting with vitality and lust, and, because his divorced parents are both sex therapists, he’s got the concepts down. A savvy classmate, Maeve (Emma Mackey), notices his talent for giving advice, and the plot unfurls from there. “Sex Education” has fun with its concept and characters while respecting them: we get to know people through their intimate vulnerabilities, alongside diagrams of genitalia and phrases like “scrotal anxiety.” As they manage their clinic and their lives, Otis and Maeve fall in love, but not at the same time. The writing and performances (many by relatively unknown young actors) are so sharp that, by the end of the first season, the status of each relationship felt like a cliffhanger.