There's no evidence that it's being treated as a joke.
The only text under each picture is:
U.S. website The Onion has named North Korean supreme leader Kim Jong Un as the "Sexiest Man Alive for the year 2012".
"With his devastatingly handsome, round face, his boyish charm, and his strong, sturdy frame, this Pyongyang-bred heartthrob is every woman's dream come true. Blessed with an air of power that masks an unmistakable cute, cuddly side, Kim made this newspaper's editorial board swoon with his impeccable fashion sense, chic short hairstyle, and, of course, that famous smile," it said.