SM Entertainment / Big Hit Entertainment

Time must move differently in K-pop. That's the only logical explanation for how BTS, some of the busiest and most famous Korean artists on the planet could put out two albums (Love Yourself: Tear and Love Yourself: Answer) — in addition to their third Japanese studio album, Face Yourself — two mixtapes (J-Hope's Hope World and RM's mono), release their first-ever English track with Steve Aoki ("Waste It On Me"), embark on a sold-out world tour, film multiple music videos, and drop a fire diss track and remix on Soundcloud all in the span of 12 months.

Or how NCT's Mark Lee, a 19-year-old Korean-Canadian with an effortless flow, could participate in a whooping nine comebacks, or new releases, this year between Neo-Culture Technology's many units: NCT 127, NCT Dream, NCT U, and NCT 2018.

SM Entertainment

Mark Lee, the hardest-working guy in NCT

In the world of K-pop, things move fast and furious. And the next release — complete with its own concept (or visual theme) and album — is just around the corner. As such, it's so easy to miss the real gems in an artist's or group's total work because the lead single is the only song that ever gets any real promotion. So much has been said about 2018 being a breakthrough year for K-pop, thanks to its growing visibility and credibility in the U.S. — and that's certainly true! — but this year was also a great year for Korean music, period.

EXO made their triumphant return with Don't Mess Up My Tempo, a layered album full of crystalline pop, and SHINee released The Story of Light, a prismatic trilogy that celebrated the group's fizzy aesthetic and eclectic sound. Meanwhile, Red Velvet refused to be put in a box with The Perfect Red Velvet, Sunmi explored the complexity of human emotion on the moody Warning, and NCT 127 continued to break the rules of convention with their first full-length album, Regular-Irregular.

So let's take a look at the work that often goes overlooked with some of the best K-pop B-sides of 2018 (in no particular order):