Language is no barrier for Japanese duo Yoasobi — music is how they communicate.

“We Yoasobi love the Korean culture, and performing live in Korea has been a dream of ours […] thank you for making our dream come true. Together, let’s keep making our dreams come true,” Yoasobi’s vocalist Ikura said, rather slowly, as she read her letter in Korean on Sunday at Korea University’s Hwajeong Tiger Dome in Seongbuk District, central Seoul.

The Japanese project group, consisting of vocalist Ikura and composer and producer Ayase, held the group’s first Korean concert on Saturday and Sunday. But something was missing: unlike many other foreign artist’s concerts held in Korea, there were no translators there to convey the duo’s message to the audience.

The concert, instead, had the duo communicating with the audience in a mix of Japanese, English and even a bit of Korean. The audience smiled and laughed lightheartedly as the members recited their memorized messages in Korean.

“Yesterday, I had yangnyeom [sweet and spicy] chicken and it was very good,” Ikura said, receiving help from the audience as she forgot the Korean word for yesterday.

But according to the duo, they didn’t have any communication issues with the Korean fans.

“We came to Korea with a strong urge to communicate, and the most important prerequisite we had in mind was to communicate through our music,” Ikura said during a press conference Monday held at the CGV Cine Library in central Seoul.

“We actually thought our fans would want to see us talk in Japanese, so we used both Japanese and English to communicate during the concert,” she said. “I was also surprised to see how much of the Korean audience understood our Japanese.”

The duo both shared that they began learning Korean as soon as they found out they would be performing in Korea.

“Similar to Ikura, I, too, tried to learn Korean myself — I even watched videos to teach myself hangul,” Ayase said. “But my memorizing skills are not good, so I didn’t manage to memorize them. And I knew if I said things without [fully] memorizing the lines, I would just end up speaking nonsense, so I wrote a letter myself and asked for a translation [into Korean], which I read with Japanese pronunciation written on it.”

Yoasobi performed a total of 16 tracks, ranging from the band’s debut song “Into The Night” (2019) — also known as “Racing into the Night” — to “Biri-Biri,” a song released in November in collaboration with hit animation and video game series Pokemon. Audiences indeed enjoyed the band’s performance, following the fan chant and singing along to many of the duo’s tracks.

“Fans singing along from the very first track to the very last is not something you would see in Japanese concerts,” Ayase said.

While sing-alongs can be seen in concerts all around the world, ddechang — Korean for singing together as a crowd — in which the audience sings along through the entire song, is a unique cultural difference in Korea.

“I expected fans would sing along to our fast-paced tracks, but I didn’t know fans would sing even the ballad tracks,” Ikura said. “Knowing [that] on the first day, I just hoped the fans would sing along even louder. So [on the second day] we were able to further communicate with our fans as we tried to lead the fans to sing along with us.”

For Yoasobi, Korean fans’ singing managed to leave a deep impression.

“It was very touching; I got so nervous listening to the singing along and I didn’t know what to do,” Ikura said. “People sang our songs even when they were in Japanese, and I tried my best to soak in all the energy and pay them back with my vocals.”

Ikura added that the band’s 2020 track “Blue,” featuring coordinated choruses, felt the loudest to her, as she heard it clearly, even with her earphones in.

Yoasobi, formed in Japan in 2018, is a unique project group where the band makes songs based on stories and novels: The duo’s debut track “Into The Night” was based on the winning novel of a Japanese web novel competition, “Blue” was based on the Japanese manga “Blue Period” (2017-), and the band’s most popular song in Korea, “Idol,” was based on the anime “Oshi no Ko” — also known as “My Favorite Idol” and its original novel “45510.”

While the band was known to fans in Japan and abroad for its unique music, “Idol” was what really rocketed the band's popularity, especially in Korea. The song sparked TikTok’s “My Favorite Idol challenge” with many Korean and Japanese fans, including top K-pop idols, uploading shorts for the challenge on the platform.

The song also became the first J-pop song to land atop YouTube Music Korea’s music chart, in July.

But despite the popularity and attention, the duo remained humble.

“I wonder why,” Ikura and Ayase said simultaneously, as they were asked by reporters why the duo was so popular in Korea.

“The way we see it is that we still have a long way to go,” Ayase said. “We’ve been saying that we like to listen to K-pop songs on social media, so perhaps that helped us relate more to the Korean fans.”

“We were so glad to see the covers, shorts and challenges, breaking the language barrier and breaking the physical barrier of being on the other side of the sea,” Ikura said.

“As Yoasobi, I do not intend to lock ourselves to a specific genre; We want to do songs in whatever genre that we can think of at the time, freely make music based on the interesting novels that we read,” Ayase said of the band's future plans.

“The concert in Korea was memorable in many ways, and I would like to meet everyone who was not able to attend the concert this time,” Ikura said.

“We hope you keep on listening to our music and keep requesting future concerts in Korea so we can come back to Korea for concerts.”

Yoasobi will continue its first overseas tour “Yoasobi Asia Tour 2023-2024” in Singapore, Malaysia and Taiwan in January.

BY CHO YONG-JUN [cho.yongjun1@joongang.co.kr]