Fan Casting Genki Girl in Sort by Tropes

The Genki Girl is a character — usually a schoolgirl, but not always — possessed of an over-abundance of energy, such that she runs everywhere (often with arms waving wildly or outstretched like airplane wings), speaks quickly (sometimes unintelligibly so), and always does everything fast, fast, fast! She's filled with confidence and determination, regardless of whether she's competent or not. To sum it up, a good way of telling whether a female character is genki or not is to see if her family and peers are exhausted, astonished, or even creeped out by her chronic outbursts of vitality. (A female character is by far the more common version, but this trope is not limited to females.)