Siti Aisyah, an Indonesian citizen, is seen smiling awkwardly as people sang her "Happy Birthday".
"And now the person next to me will become a (celebrity)," one friend says in the video she filmed that night, prompting Aisyah to laugh.
The scenes are in stark contrast to those shown on security footage from the next morning, February 13, when police say Aisyah and a Vietnamese woman, Doan Thi Huong, approached Kim Jong Nam as he passed through terminal 2 of Kuala Lumpur airport.
'Naive and easily manipulated'
The footage was filmed by Aisyah's friends and given to CNN. Three days after the celebrations in the restaurant, Aisyah would be in custody along with Doan Thi Huong, from Vietnam. Police say the two women were identified in the airport security footage.
Authorities from Aisya and Doan's home countries say both women maintain they thought they were part of a TV prank show. Aisyah thought the substance she rubbed on Kim's face was "a kind of oil, baby oil, something like that," said Andreano Erwin, Indonesia's deputy ambassador to Malaysia.
Another friend, who spoke to CNN on condition of anonymity to protect her privacy, said Aisyah was "naive" and easily "manipulated."
"Whatever that people said, she would believe. She would only follow," the friend said.
The friend, who has known Aisyah for two years, said she was a "friendly" woman but sometimes kept things to herself.
"For things involving work, she did not say. We don't know (her job). She keeps her privacy. Maybe because it never came up in our conversation," the friend said.
'Happy birthday'
Aisyah's friends told CNN they wanted to help her celebrate her birthday, and chipped in to pay for the dinner. Footage from the night shows elaborate drinks and large steaks.
In one video, Aisyah blows out the candle on her birthday cake while everyone in the room cheers and bangs their cutlery on their glasses.
In the background, "Miracle Mile" by the Cold War Kids plays as the camera pans over the food. "I was supposed to do great things," the song blares.
Salhan K Ahmad in Kuala Lumpur contributed to this report.