Avid viewers of tvN's latest hit "Lovely Runner" may have felt their hearts break when the series ended on Tuesday. But it was the same for lead actor Byeon Woo-seok, who said that bidding farewell to his character, Ryu Seon-jae, gave him "mixed feelings."

“I’m not ready to leave Seon-jae behind,” Byeon said in an interview with the local press on Wednesday at a cafe in southern Seoul after the final episode of the series aired on Tuesday. The finale scored a 5.8 percent viewership rating, marking its highest rated episode.

“I truly loved my character, so it's surreal that everything is now over.”

The series follows Lim Sol, portrayed by actor Kim Hye-yoon, as she travels back 15 years in time to prevent the future death of Seon-jae, a member of fictional rock band Eclipse.

It has become one of the most popular dramas this year thanks to its deep love story, in which Seon-jae falls in love with Sol no matter what. Seon-jae's "pine-like personality," according to the actor, created hundreds or even thousands of Seonchinja, meaning people who are obsessed with Seon-jae. The drama's pop-up store had a bustling queue even before it opened on May 23 at The Hyundai Seoul department store in Yeouido, western Seoul. Fans were even swarming outside the cafe where the interview was held just to catch a glimpse of the star.

All the attention he has been receiving thanks to "Lovely Runner" has given him nothing but an overwhelming sense of gratitude, said the 32-year-old actor. Byeon reportedly burst into tears during a viewing event for the last episode held in central Seoul on Tuesday, where the series' cast, staff and fans watched the final episode together.

“Though I’m the one who is receiving all the love, it was made thanks to the immense effort that the drama staff put into the work, trying to make the scene the best it can be,” said a humble Byeon. “It has been a while since I last saw everyone, and seeing them there at the series' end, my emotions just burst out.”

Byeon, who first debuted as a model in 2010, kicked off his acting career in 2016 with the tvN drama “Dear My Friends” (2016). Though it has been years since he stood in the public eye, Seon-jae was the star’s first series' lead role — a successful one indeed, but not an easy character to build, according to the actor.

“When I had to prepare for scenes as a K-pop star, like holding a concert, I questioned myself whether I could smoothly carry out my role,” Byeon said.

The members of Seon-jae's fictional rock band Eclipse actually helped him overcome his worries. Seon-jae is the vocalist of Eclipse and actor Byeon actually sang the song "Sudden Shower" in the show.

“I thought that I should let them do all the work, while doing my best," he said. "Thanks to them, I was able to act for the scenes with more confidence, knowing that they were beside me.”

But all his worrying was for nothing. Not only did "Sudden Shower" land on the top 10 popular charts of online music streaming sites, such as Melon, the internet was filled with people applauding Byeon's vocal skills. This added to the depth of the drama itself.

“I always dreamt of singing an original song for a drama that I act as a main character in, and I had the opportunity to do so in my first main character role. I enjoyed every moment of it," he said.

Byeon also revealed a secret about Seon-jae that wasn't shown in the drama.

“The reason Seon-jae liked to swim was because of his sick mother, who he saw become happy after he won a prize,” the actor said. "I wanted to express his strong desire for swimming, hoping that the viewers would also sympathize with Seon-jae's circumstances."

Singing in a drama was not the only new experience for actor Byeon while playing Seon-jae. The character also made the actor believe in destiny.

“I think I started to believe in the term destiny while playing Seon-jae,” Byeon said. “So many things happened while making the series. And being able to finish the series, passing all those circumstances, ‘destined’ may be the word that can explain it. I’m not sure how to explain it. I think I was really really lucky.”

Following the hit series, Byeon’s popularity is soaring high, which was shown by the 8,000-seats of his Seoul fan meet and greet selling out in minutes. Fans complained about the number of seats being too few.

“I couldn’t believe it, seeing the number of people waiting online. At first, I thought it was 50,000 people, but I later realized that it was 500,000.”

“[If everybody] stands for me in the future as well, I’ll do my best to find a bigger place next time,” Byeon added, asking the reporters in the cafe to please deliver his message.

It seemed that the actor was also soaking up and enjoying every moment of the attention he is receiving, saying that he doesn’t want to go back in time, as the series has ended.

“The emotions that I felt by coming this far with Seon-jae are things that I don’t want to lose," he said. "I want to treasure these good emotions.”

Like Seon-jae, who puts his utmost in everything, Byeon also wants to be an actor who puts all that he can into his work.

“You know that when a person gets a perfect score on a test, they keep wanting to get that score. Like this, I thought that I should do my best and do better when I do my next project.”

To find out more about Byeon Woo-seok, visit Celeb Confirmed!

BY KIM JI-YE [kim.jiye@joongang.co.kr]