The seven members of BE:FIRST, ranging in age from 17 to 26, command the stage, having sold out Japan’s famed Tokyo Dome multiple times. Off stage, the group, consisting of members Sota, Shunto, Manato, Ryuhei, Junon, Ryoki and Leo, is full of excitable energy. Next week, the group’s newest single, “Sailing,” is set to drop. The song, a collaboration with the wildly popular animated series One Piece, will serve as the ending theme for a newly edited version of the show’s Fish-Man Island story arc. One Piece Log: Fish-Man Island Saga, an “abridged 21-episode story,” according to Crunchyroll, was originally set to premiere on Oct. 27 but was pushed to Nov. 3 due to live broadcasts of the MLB World Series. “We are big fans of One Piece, and we are very happy to be able to do the ending theme song because we have been telling everybody that we really, really love One Piece,” BE:FIRST’s youngest member Ryuhei tells The Hollywood Reporter. The 17-year-old says that the group tried to not make the song just One Piece or just BE:FIRST, but they instead made it a combination of the two. One Piece Eiichiro Oda/Shueisha, Toei Animation “Sailing” is an upbeat song that evokes the feeling of sailing along the open sea, perfectly fitting for the song and show. The lyrics of the song speak of being a family and pushing through tough times together, something that ties into the show and the group. “We connected everything to the lyrics itself,” Sota says. The 23-year-old explains that he, Shunto and Ryuhei wrote the song’s lyrics, along with their company’s CEO and producer, SKY-HI. “The BE:FIRST and One Piece connection is very deep,” he adds. For nearly all of the group, One Piece has been a part of their lives since childhood. Manato says he started vocal lessons with K-pop group TVXQ’s One Piece song, which led him to dream of being a vocalist. “It’s kind of destiny,” the 23-year-old says. “We have been big fans since childhood,” Shunto says. “We really wanted to do this kind of collaboration together in the future, but we didn’t think that we could do this so soon after our debut.” Earlier this year, the group performed for the first time in front of U.S. crowds, opening for K-pop boy group ATEEZ at their Los Angeles stadium shows. The two boy groups recently collaborated on two songs together. Leo says the highlight of the U.S. trip was his ability to communicate with the local team. He jokes that he was able to learn English slang during the trip, putting it into his solo music. “We made these songs [that they performed in L.A.] not just for a Japanese audience but also worldwide,” Ryoki explains. “That’s why we had confidence enough to perform in L.A.” The 25-year-old says that the crowd during the L.A. show had good vibes and that it was a perfect performance for them, which got them thinking that they might be able to perform their own show in L.A. or elsewhere in the U.S. BE:FIRST is gearing up for a big finish to the year and big start to the next. The group is planning to embark on a dome tour around Japan. They’re also hoping to expand their touring reach in the future. “We really want to do a live tour around the world,” Leo says. “We want to deliver our music to all the fans.”