Psy and IU are undoubtedly two of the most popular and well-loved K-pop artists of today's generation. Having massively succeeded in his "Gangnam Style" and has enchanted millions of people thanks to her soft and tender voice that perfectly matches her beauty, Psy and IU are indeed very talented.
This is the reason why they have reached so much fame not only in South Korea but throughout the whole world as well. In the episode, Psy and IU took the chance to engage in music collaboration as they sang and performed "What Would Have Been" in perfect harmony with each other.
According to All K-pop, the song has been included on the 6th album of Psy. Though the song features a different tempo and theme than IU's usual soft voice, the K-pop idol still managed to ace it when she performed the song together with Psy.
According to Ask K-pop, in the duet, it can also be seen that Psy perfectly blended with IU's vocal prowess. It's as if they have a connection with each other that is not present in other K-pop music collaborations. With this, one can speculate that there might really be something happening between the two.
Perhaps, there is something romantic present between them. Despite the lack of evidence, people can see how their facial expressions and gestures during the performance seem to really be different. For now, there is no strong evidence that they might really be dating. It's also impossible when considering a lot of factors.
Knowing that Psy is already married and that there is a huge gap between them, it seems unlikely that there's something romantic between them. Let's just wish them the best of luck and hope that they get to work together for more music collaborations in the future. They sure can make it once more.