Hong Kong (CNN) -- So little is known about North Korean leader Kim Jong Un that the identity of a woman seen by his side during more than one official engagement has sparked a flurry of speculation worldwide.
Was the slim woman in the sharp black suit his sister, wife or even lover?
No one seems to know, and Andrei Lankov of Kookmin University in South Korea, an expert and author of a number of books on North Korea, said it was unlikely speculators would ever find out.
"Everything related to Kim Jong Il's children is a deadly secret. No sane North Korean who knows it would share this out for very special reasons," Lankov said.
The mystery woman accompanied the young leader to a Pyongyang theater on Friday night to watch a performance of North Korea's Moranbong band. The display included a cast of Disney characters, attracting the attention of The Walt Disney Company, which issued a statement Tuesday saying it had not authorized their use.
Away from the stage, the young woman's presence raised questions too about the purpose of the performance and the message the leadership was intending to convey.
A statement released by the North Korean Central News Agency (KCNA) Saturday made no mention of either the Disney characters or the woman who was seen in official photos distributed worldwide standing and clapping at the end of the performance.
Friday's outing wasn't her only high-profile appearance at the North Korean leaders' side.
The same woman was seen on state TV Sunday walking a few paces behind Kim as he toured Kumsusan Palace in Pyongyang, then standing to attention at Kim's side as they and top military officials paid tribute to his grandfather Kim Il Sung, North Korea's founding father, on the anniversary of his death.
The presence of a female companion to the leader during an official engagement was unusual, Lankov said, and could be part of a campaign to present Kim as "much more approachable, human-like and soft on people" than his father, Kim Jong Il.
"He travels much more than his father and even than his grandfather. He likes to hug everybody, physically hug. In this regard it's probably he decided that it might be a good idea to hint that he does have a wife," Lankov added.
Definitely a wife, Lankov stressed, because the public appearance of a leader's girlfriend or lover would be unthinkable. Even the wives of his father and grandfather stayed firmly in the shadows during their decades in power.
"When his grandfather's first wife, if you like the founding mother of the dynasty, was alive, her name was never, never mentioned in media. Her existence was never even hinted at," Lankov said.
There was no reference to Kim Il Sung's first wife before her death and for many years there was no mention at all of his second wife, Lankov added. "It took 15 years before the existence of his wife, his second wife, was ever mentioned in press," and even then it was in passing, he said.
In South Korea, the image of Kim's companion made newspaper headlines. A report in South Korean daily Chosun Ilbo said the woman "seemed to be" Kim Jung Un's sister, Kim Yeo Jung.
"Born in 1987, Yeo-jong is now in her mid-20s. She apparently went to a school in Switzerland along with Jong-un in the 1990s," the newspaper's website said. Her brother Kim came to power in December 2011 after the death of their father, who led the impoverished country for 17 years.
Very little was known about Kim when he was granted the title of supreme leader; his age is still a source of speculation, though it's thought he's in his late twenties.
"Three years ago the only thing we knew about him was his existence," Lankov said. "Until, say 2010, as far as I remember we didn't even know how his name was correctly spelt in Korean."
Lankov said it was too early to say whether the tweaks to Kim's public image indicate change ahead for the country.
"This appears to be the beginning of some change, but what it's too early to say. It might just be a minor change in style. It might be something more consequential, I don't know. I would not speculate right now," he said.