/ ˌdɔːriən ˈgreɪ; NAmE / noun
[ usually sing. ] a person who continues to look young and beautiful, even though they are growing older or behaving in an immoral way :
He's a real Dorian Gray, apparently untouched by the ageing process.
ORIGIN: From the story by Oscar Wilde, The Picture of Dorian Gray , in which Dorian Gray is a beautiful young man who behaves in an immoral way. He secretly keeps a painting of himself, which gradually changes, making him look older and more evil in it. Dorian himself continues to look young and beautiful.