TAEYONG and HAECHAN's 'Bitter Sweet' Is the Addictive OST Nobody Expected

NCT's TAEYONG and HAECHAN have dropped one of 2026's most unexpectedly irresistible K-drama OSTs with "Bitter Sweet (Addiction)" — the second soundtrack entry for the hit tvN weekend drama Mad Concrete Dreams (대한민국에서 건물주 되는 법). Released on March 29 at 6 PM KST across all major streaming platforms, the track arrived exactly when drama fans needed it most: right in the middle of a run that has made the show appointment viewing for Korean audiences.

What makes this collaboration so compelling is the genre choice. Rather than a predictable ballad, the production team leaned fully into Funk House — a rhythmically charged, groove-heavy sound that lands somewhere between late-night dance floor and cinematic swagger. The result is a track that doesn't just accompany the drama; it becomes inseparable from it.

The Sound: Funk House With an Addictive Core

"Bitter Sweet (Addiction)" is built on a punchy bassline and an upbeat drum groove from producer 808MALC, whose fingerprints are all over the arrangement. The composition credit also includes Leroy Sanchez, Stalking Gia, and Flash note, creating a layered production that rewards repeat listening. A groovy percussion section and an intoxicating bass riff thread through every bar, while a chant hook after the chorus is the kind of earworm that lives in your head for days — which, given the title, feels entirely intentional.

Lyrically, the song channels the spirit of the drama's central character: someone pushing through the bitterness of an unforgiving reality to find new opportunities. Written by ONE.KI, 808MALC, Leroy Sanchez, and Stalking Gia, the lyrics resist the melodrama often associated with K-drama soundtracks and instead opt for something more defiant — a declaration of resilience wrapped in a genre that makes you want to move.

The track was recorded at Vibe Music Studio 606 by 이강현 (kanghyun_LEE), digitally edited by 권유진 at doobdoob Studio, mixed by 신봉원 at GLAB Studios, and mastered by 권남우 at 821 Sound Mastering — a full production chain that gives the final release a crisp, club-ready finish.

The Drama: Mad Concrete Dreams Is Must-See Weekend Television

Mad Concrete Dreams airs every Saturday and Sunday at 9:10 PM KST on tvN and has been turning heads since its premiere. Written by Oh Han-gi and directed by Lim Pil-seong, the drama is produced by Studio Dragon and Mind Mark — a combination that signals top-tier production values from the outset. The story follows characters caught in the gap between ambition and reality in modern Korea, where the dream of becoming a property owner (건물주) serves as both a literal goal and a metaphor for the broader desire to secure a stable, successful life.

OST placement within such a drama carries weight. The first OST for the show set a high bar, and Stone Music Entertainment — the distributor behind this release — clearly chose TAEYONG and HAECHAN with that standard in mind. The chemistry between the two NCT members and the drama's themes is not accidental. Their vocals carry both the sweetness and the edge that the show demands.

Why TAEYONG and HAECHAN Work Together

Within NCT's expansive roster, TAEYONG and HAECHAN represent two distinct but complementary vocal identities. TAEYONG, who debuted with NCT in 2016, is primarily known for his rap precision and stage presence, but has consistently expanded his vocal palette through solo works and collaborative projects. His approach to melody is controlled and deliberate — every note placed with intent.

HAECHAN, widely regarded as one of NCT's most technically gifted vocalists, brings warmth and power that anchors any track he appears on. His ability to ride a groove without losing emotional depth is exactly what a Funk House production demands. Where TAEYONG adds edge, HAECHAN adds resonance, and the two find a shared pocket in "Bitter Sweet (Addiction)" that feels natural rather than forced.

For fans who have long hoped for an official TAEYONG-HAECHAN collaboration outside of their full-group activities, this OST is a satisfying answer to that wait. The fact that it comes wrapped in a genre as dynamic as Funk House only sweetens the deal.

Fan Response and Chart Trajectory

From the moment the OST announcement landed on March 27, fan communities on Twitter/X, Weverse, and Melon's comment sections lit up with anticipation. The phrase "Funk House" in the track description alone was enough to generate excited threads across K-pop forums, with many noting that neither TAEYONG nor HAECHAN had tackled the genre in this capacity before.

Post-release on March 29, listener responses confirmed the pre-release energy was justified. Comments described the bass riff as "impossible to skip past" and the chant hook as "the part that gets stuck in your brain at 3 AM." The track charted on Melon within hours of release, a testament to both the duo's dedicated fanbases and the OST's standalone appeal beyond drama viewers.

K-pop fans outside the NCT fandom also noted the track's quality, with several Spotify and Apple Music playlists in the K-drama OST space already featuring the song. On YouTube, the official MV quickly accumulated views on Stone Music Entertainment's channel, with comment sections filled with requests to see live performances of the song.

The OST Strategy Behind Mad Concrete Dreams

Pairing idol group members with premium drama productions for OST contributions has been a well-worn strategy in the Korean entertainment industry, but the execution matters enormously. A mismatch between an artist's sonic identity and a drama's emotional register can feel jarring — which makes the choice of TAEYONG and HAECHAN for a Funk House track tied to a drama about defiant ambition feel particularly well-considered.

Stone Music Entertainment has a long history of curating OST contributions that amplify rather than merely accompany the source material. Their decision to lean into an upbeat, rhythmically aggressive genre for Part 2 of the Mad Concrete Dreams soundtrack suggests confidence in both the artists and the audience's appetite for something unexpected.

OST Part 1 laid the groundwork; Part 2 delivers the hook that keeps listeners coming back. With the drama's weekend run ongoing, more soundtrack entries are likely to follow — but "Bitter Sweet (Addiction)" has set a high standard for what comes next.

"Bitter Sweet (Addiction)" by TAEYONG and HAECHAN is now available on Melon, Genie, Bugs, Flo, and major international streaming platforms including Spotify and Apple Music. The official MV is live on Stone Music Entertainment's YouTube channel.