Japanese heartthrob Kentaro Sakaguchi said he thought the cultural distinctions in how people express affection, played a crucial role in his Korean debut series "What Comes After Love."

The six-part Coupang Play original series portrays the romance between Choi Hong (Lee Se-young) and Aoki Jungo (Sakaguchi), who unexpectedly reunite five years after their breakup. The series is based on the novel of the same name, co-authored by Korean novelist Gong Ji-yeong and Japanese writer Tsuji Hitonari.

Sakaguchi is one of the most cherished Japanese actors in Korea, winning fans with his appearances in "The Last 10 Years" (2022) and "Signal: Long-Term Unsolved Case Investigation Team" (2021), the Japanese remake of the popular Korean mystery series "Signal."

According to Sakaguchi, the cultural differences between Japan and Korea were essential to the story, with a key example of how it affected the series being how the main characters expressed their feelings for each other.

"When I read the script, I noticed there were a lot of 'I love you's,' and I wasn’t sure if that was due to a cultural difference. I think there's a more ambiguous, in-between feeling that exists between 'I love you' and 'I like you,' but this script was full of 'I love you,'" said Sakaguchi, during a group interview held on Sept. 13.

"I suggested to the director that 'I love you' is a powerful and significant phrase, so it might be better to reduce its use. However, both the director and Lee Se-young felt that my character should actually be saying it more often," he said.

Sakaguchi said his suggestion ultimately led to a reduction in the use of the phrase.

"I believe (such) cultural differences got to play a crucial role in the series. (Hong and Jungo's) separation was inevitable because of these differences, and if they had expressed their love, they might not have parted, which means that this series wouldn’t have existed at all," said Sakaguchi.

Sakaguchi's cultural observations extended beyond the script.

When working on "What Comes After Love," which marked his first experience at a Korean production site, Sakaguchi said he noticed significant cultural differences between Japanese and Korean production environments, with one notable difference being that at a Korean production site, everyone was present at the same time, supporting and cheering for one another.

"For example, on the days when Se-young or I were filming, the others didn't need to come, but everyone showed up to offer their support," said Sakaguchi.

"I was also surprised to see the director's friends come out to support us as well. Thanks to those people, I felt encouraged," he said.

Regarding Sakaguchi's future career in Korea, the Japanese actor expressed his enthusiasm for participating more in K-content.

In particular, he shared his wish to act alongside Park Bo-gum, with whom he has a personal connection.

"Although we haven't worked together yet, I’ve had the chance to meet and talk with Park whenever I visit Korea. Building trust is important when working together, and since I have that relationship with Park, I would love to collaborate if the opportunity arises," he said.

The first two episodes of "What comes after love" will stream on Coupang Play on Friday.