A viral moment involving South Korean actor and singer Seo In Guk has gotten a lot of people talking online after screenshots from a promotional video made fans remember an unexpected part of his career history.

In this clip from a Netflix promotional video, Seo In Guk and Jisoo discuss their new show, "Boyfriend on Demand." The screenshots and conversation quickly spread across social media, drawing attention to Seo In Guk's singing skills and making people laugh.

Koreaboo says that some screenshots from the video went viral after people reacted to the actor's singing. Some people who commented seemed surprised by how well he sang and even compared him to other famous entertainers.

A person who saw the video online said, "Wow, Seo In Guk is really good at singing. Park Bo Gum is good too, but Seo In Guk sings like a real singer."

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Another comment going around online said that some people were even more shocked to learn about his past, focusing mostly on his identity as an actor rather than a musician.

Another person on the internet said, "What? He's the person who is amazing for being so good at acting."

The screenshots quickly spread through Korean online communities, where people started making fun of Seo In Guk when they found out that he really did start his career in music. There were many posts on the online forum theqoo that put these two reactions together.

People on this online forum mentioned how funny it was that individuals were surprised at his ability to sing, pointing out his past successes.

Someone said, "Guys...he's the winner of 'Superstar K' LOL."

Another person made it clear who he was by saying, "He's not just any singer, but the winner of the singing survival show 'Superstar K'."

Many comments also pointed out how long it has been since Seo In Guk actively promoted music. This could be why some people only consider him to be an actor.

One comment said, "He debuted as a singer LOLOLOL."

Another person on the internet found it funny and wrote,"What do you mean he sings like a singer..."

Other comments said the same thing, with one saying, "Obviously...because he is a singer."

Someone else said, "I almost forgot he was a singer LOL...he hasn't promoted any music in so long."

Seo In Guk became famous in 2009 when he won the first season of Superstar K. Later, he switched to acting and made his debut in 2012. He became known for a wide range of TV roles.

The viral moment has since reminded fans of the entertainer's musical roots and shown how stars can end up in acting careers in ways that are sometimes surprising.

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