She and Kim Yong Nam, the North's 90-year-old nominal head of state, were seated behind Moon and his wife, while Pence and his wife were seated beside the Moons and Japanese Prime Minister Shinzo Abe.
But away from the spotlight, these two unwanted guests, men dressed as North Korea supreme leader and the USA president, were escorted away from the premises.
American luger Erin Hamlin said it was "too bad" that there was disappointment about her carrying the United States' flag at the Winter Olympics opening ceremony and that any athlete would have felt honored to accept the task.
Asked whether it was hard for him to see Jong Un's sister sitting behind Vice President Pence at the Opening Ceremony, Mr. Warmbier said: 'No, she's in the Kim family, ' suggesting that he did not attribute the same blame for his son's fate to her as he does to her dictator brother.
Earlier on Saturday, South Korea's Choi Minjeong set an Olympic record in the women's 500m with a 42.870-second finish in her heat to qualify for the quarter-finals taking place on Tuesday.More news: Pelosi To Vote 'No' on Budget, But Won't Whip Caucus
The handwritten invitation to President Moon was delivered by Mr Kim's influential sister, Kim Yo-jong, at a landmark meeting in the presidential palace in Seoul, as the Games opened on Saturday.
Moon recalled his past visit to the North's Diamond Mountain resort, where he and his mother met his North Korean aunt during a temporary reunion of families separated by the 1950-53 Korean War.
'When you put it that way, they're not really participating in the Olympics. The South Korean forward Han Soo-jin contributed the team's most aggressive attempt in the whole game, but her efforts were in vain with the puck hit the net "roof". North Korea boycotted the 1988 Summer Olympics in Seoul and blew up a South Korean commercial airliner the year before.
North and South Korean athletes enter together under the Korean unification flag during the parade of athletes.
The four senior DPRK delegates will have a meeting and lunch with President Moon on Saturday, according to South Korea's presidential Blue House.
President Donald Trump's administration has taken a hard line on North Korea's nuclear and ballistic missile program, saying there is no room for negotiations unless Pyongyang abandons it. While both the naturalized and South Korean-born players used English words for basic ice hockey terms such as "shoot", "pass" and "change", the North Korean players did not use any English terms.
Wary that the North is trying to drive a wedge between Washington and Seoul, he made a point of having no part of any of the North's brand of for-Koreans-by-Koreans detente.