jailbait

/ˈdʒeɪlbeɪt/

IPA: /JH EY1 L B EY1 T/

noun
  1. 1

    A sexually mature person (usually female) below the legal age of consent who is regarded (usually by an adult male) as being attractive and/or seductive.

Source: https://en.wiktionary.org/wiki/jailbait