[Photo &] Sung Si-kyung Makes Surprise Appearance at Kim Kwang-jin Concert... Praised for His "Prime Time Looks"

Singer Sung Si-kyung made a surprise appearance as a guest at senior Kim Kwang-jin's encore performance, showcasing his exceptional loyalty.

On February 25, 2026, Kim Kwang-jin expressed his gratitude on his SNS, saying, "After appearing on 'I Will Sing', Si-kyung, who sold out the Lotte Concert Hall, made a surprise guest appearance at the encore concert and made the audience happy."

He continued, "Thank you so much. A shot with Si-kyung and Hyun-jeong at the after-party," along with a photo. Notably, Kim Kwang-jin added, "But Si-kyung's face looks like he time-traveled back to his prime," praising Sung Si-kyung's unchanged visuals, which caught attention.

In the released photo, Sung Si-kyung, Kim Kwang-jin, and their friend Hyun-jeong are wearing glasses and smiling brightly. The friendly appearance of the three suggests the warm atmosphere of the event. Fans are also showing a hot reaction to the news of Sung Si-kyung's surprise appearance.

Meanwhile, this successful encore performance by Kim Kwang-jin was held in a space that has been transformed into a concert-exclusive theater, remodeled from the former famous 'Myunghwa Nightclub' in Yeongdeungpo, adding to its significance.