Question

A conspicuous element or pattern, such as a type of event, device, reference, or formula, which occurs frequently in works of literature.

Answer 1

It is called "Motif".

Motif is a repeating component that makes conspicuous examples in old stories and society craftsmanship customs for example, the "loathly lady" who ends up being an excellent princess is a typical motif in old stories, and the man lethally charmed by a reasonably woman is a motif received from old stories in Keats' "La Belle Dame sans Merci".