The footage was released by the South and North Development Institute - or SAND - which works with North Korean defectors.
Reuters was unable to independently verify the footage, which was first reported by the BBC...
and has blurred the names and faces of the students as requested by SAND to protect their identities.
Choi Kyong-hui is the President of SAND. She defected from North Korea in 2001.
Choi said the video serves as an "alarm and warning."
"I think probably this video was edited in around 2022. The North Korean leadership makes the video, and then each organization within the country gives lectures and the people get educated with them. In the middle of this process, the video was filmed by an insider in 2023 with a mobile phone, as mobile phones are now also popular in North Korea."
She said it also indicates how South Korean culture is "quite widespread" and that millennials and Generation Z are the biggest headache for leader Kim Jong Un.
North Korea has for years imposed tough sentences on anyone caught enjoying South Korean entertainment or copying the way South Koreans speak...
in a war on outside influences since a sweeping new "anti-reactionary thought" law was imposed in 2020.
According to the video... the two 16-year-olds were sentenced after being convicted of watching and spreading South Korean movies, music and music videos over three months.
"They were seduced by foreign culture... and ended up ruining their lives," says the narrator in the video.
North Korea and South Korea are technically still at war after their 1950s conflict ended in a truce, not a peace treaty, and are divided by a heavily fortified demilitarized zone.
