Lolita was the nickname of one of the principal characters in Vladimir Nabokov's novel Lolita. Lolita's actual name was Dolores, with whom the narrator, Humbert Humbert, develops a sexual obsession. In the book itself, "Lolita" is specifically Humbert's nickname for Dolores. Nevertheless, "Lolita" and "loli" has come to be used as a general reference to girls considered sexually precocious.
In the marketing of pornography, "lolita" is used to refer to a young girl, frequently one who has only recently reached the age of consent, appears to be younger than the age of consent, or child exploitation material depicting the sexual abuse of children.
Nubile is a flattering term for youthful and sexy young women who deemed attractive and "suitable for marriage". Nubile stems from an ancient Latin term which meant "marriageable." While nice young men are certainly marriageable, the term is solely used in relation to women, and now refers to their ripe sexual beauty, not necessarily qualities that could make them a dependable, loving wife.
A nymphet is a sexually precocious, pubescent girl.
The first recorded use of the term "nymphet", defined by The Century Dictionary as "a little nymph", was by Drayton in Poly-Olbion I. xi. Argt. 171 (1612): "Of the nymphets sporting there In Wyrrall, and in Delamere."
In Lolita, "nymphet" was used to describe the 9- to 14-year-old girls to whom the protagonist is attracted, the archetypal nymphet being the character of Dolores Haze. Nabokov, in the voice of his narrator Humbert, first describes these nymphets in the following passage:
Now I wish to introduce the following idea. Between the age limits of nine and fourteen there occur maidens who, to certain bewitched travelers, twice or many times older than they, reveal their true nature which is not human, but nymphic (that is, demoniac); and these chosen creatures I propose to designate as 'nymphets.'