Etymology: < Latin ephēb-us, < Greek ἔϕηβος, < ἐπί upon + ἥβη early manhood.Ancient Greek Hist.
Among the Greeks, a young citizen from eighteen to twenty years of age, during which he was occupied chiefly with garrison duty. (OED)
"The summer before his senior year of college, in 1997, he worked as an intern at The Paris Review. James Linville, who was then the magazine’s editor, recalled Rowan as an 'ephebe type, almost Truman Capote-like.'"
- Lizzie Widdicombe, "The plagiarist's tale: the author of 'Assassin of Secrets' had a secret of his own", 13 & 20 February 2012 The New Yorker
There must be an additional connotation here that I'm not picking up on.