'Kilig' is a Filipino word with no exact English equivalent — it describes the fluttery, giddy, butterflies-in-the-stomach feeling you get from a romantic moment, whether in real life or in a film or book. If your teen says a TV scene gave them 'kilig', they mean it made them swoon. It is positive, light and harmless. The word has spread globally through Filipino dramas (teleseryes) and K-drama fandoms online. No need for concern — it is a wholesome reaction, much like the English 'aww!' but specifically for romantic giddiness.