The cast of 'Cool Kids' spent the day with students from Seoul National University.

On the February 17th episode, the cast met up with three students from Seoul National University College of Medicine. As they talked about the popularity of 'SKY Castle', the students shared their real-life stories of applying to a prestigious school such as Seoul National University.

When asked what they did for "fun", they answered that they only enjoyment they always granted themselves was watching 'Infinity Challenge' and 'Running Man' every week. "Then (after watching the episode), we would continue to study," said one student.

MC Yoo Jae Suk, who appeared on both of those variety programs, shared how "proud" he felt for the boys.

The three students were also asked if they ever dated and, in fact, the question had been sent in by SF9's Chani, who played the character Woo Joo from 'SKY Castle'!

Out of the three students, only one of them had a girlfriend as of now. He shared, "we were friends ever since we started attending medical school together, then developed feelings for each other when we supported each other through demanding studies." The girlfriend, who was a Korean student who had previously studied in Vietnam, also made an impromptus appearance on the spot.

Check out all the footage above and below!