On the evening of the March 10, at the KSPO DOME in Songpa-gu, Seoul, the final performance of IU's solo concert, '2024 IU H.E.R. WORLD TOUR CONCERT IN SEOUL', took place, with a special appearance by actor Park Bo Gum.

IU, addressing the crowd during the concert, expressed her excitement over having a special guest. She teased, "I've brought a reliable and cool friend. He's not a singer, but he sings as well as one. And, even if you see him on screen and think he's incredibly handsome, seeing him in person will make you rub your eyes in disbelief." IU then introduced her guest, calling him a "wonderful and friend she's grateful towards."

The surprise guest turned out to be none other than actor Park Bo Gum. Greeting the audience, Park Bo Gum said, "Hello to all Uaenas; it's genuinely nice to meet you."

IU continued, "It might be burdensome for someone who isn't a singer to take on the stage, but I'm grateful. He's a friend I genuinely, really like. I didn't want to leave without introducing my best friend to all of you. Have a great time together, friends." Park Bo Gum added, "Though I might feel a bit embarrassed, I hope it's a happy time, just like Uaena's day."

The duo then performed a rendition of IU and HIGH4's "Not Spring, Love, or Cherry Blossoms." Park Bo Gum shared his reasons for joining the tour, saying, "I came to support the start of the world tour and the finale in Seoul. Throughout the past year, while shooting 'When Life Gives You Tangerines' with IU, I saw her diligently prepare for the world tour alongside her drama filming. Witnessing her dedication, I thought she was an amazing, impressive, and diligent friend. I'm grateful to have met such a friend."

After performing the song "Let's Go See the Stars" by Jukjae, Park Bo Gum concluded his appearance by expressing his gratitude and bidding farewell, "Wishing you all shiny and bright days. Thank you. This was Park Bo Gum, a friend of the singer IU." The unexpected collaboration added a delightful surprise for both IU and Park Bo-gum's fans attending the concert.