DK and Seungkwan of SEVENTEEN have proven the lasting power of a classic ballad. Their unit track "Blue" has climbed to No. 1 on Korea's YouTube Trending Music chart.

The duo released their first mini album Twilight Serenade on January 12. The title track entered the chart at No. 27 on January 13, steadily rising through the winter mood before reaching No. 1 on January 18—just three days after hitting No. 2.

The album's momentum extends beyond the title. B-side tracks "Rockstar" and "Guilty Pleasure" charted at No. 28 and No. 30 respectively, underscoring the unit's broad digital impact.

Live stages have been central to the song's popularity. DK and Seungkwan delivered emotional performances on Mnet's M Countdown and KBS2's The Seasons, highlighting their vocal chemistry and restraint.

A wave of vocal challenges amplified the buzz. Artists including Lee Mujin, Younha, Davichi, Sohee of RIIZE, Gummy, and Daybreak reinterpreted "Blue" in their own styles, drawing attention across platforms.

An epilogue version of the "Blue" music video arrives on January 19. Shot in Hokkaido, Japan, the visual leans into a quiet, wistful atmosphere that complements the song's tone.

Fans will also be able to experience the release in analog form. Twilight Serenade will be pressed on vinyl and released on March 16. The album surpassed half a million copies sold on its first day.

At its core, Twilight Serenade traces the fragile moments between meeting and parting. Framed as a story of "ordinary love," the record delivers an intimate message that resonates through understated storytelling and heartfelt vocals.