Throughout the years, K-Pop has gifted fans with some of the most iconic and talented groups. As wonderful as these groups may be, however, sometimes there are constraints to the music they put out: maybe it’s a predetermined group image, or tight schedules that don’t allow for experimentation, or a myriad of other reasons. So what happens when artists or companies want to push the boundaries a little bit? Sub-units! That’s why this week for Throwback Thursday, we’re bringing you some of the best K-Pop sub-units around.

“내일, 오늘 Tomorrow, Today” - JJ Project

Consisting of GOT7’s JB and Jinyoung, JJ Project actually debuted as a duo in 2012, well before becoming part of GOT7 when the group debuted in 2014. “Tomorrow, Today” comes off their 2017 EP suitably titled Verse 2, and it is a beautiful song about having lost one’s way. The song is quite different from GOT7’s usual sound, but JB and Jinyoung’s voices suit this pop-rock track perfectly. Give it a listen on those days when you need a little extra guidance.

“Twinkle” - Girls’ Generation-TTS 

Girls’ Generation-TTS—also known as TaeTiSeo—debuted as a sub-unit of Girls’ Generation in 2012. Made up of group members Taeyeon, Tiffany, and Seohyun, TTS came to be when the rest of Girls’ Generation pursued other endeavors. The sub-unit focuses more on the girls’ vocals—an obvious decision looking at their debut track, “Twinkle.” A glam-pop song with a hint of retro, “Twinkle” lets the girls sparkle in every way. From their high notes to their dresses, it’s only fitting for three of the biggest stars of the time. “Twinkle” even led TTS to be the first sub-unit to win a triple crown on music shows.

“Whisper” - VIXX LR 

VIXX LR is the first sub-unit of VIXX, consisting of main vocalist Leo and main rapper Ravi. The pairing may seem somewhat surprising to some, but the two balance each other perfectly in their releases. “Whisper” comes off their 2017 sophomore mini-album of the same name and is easily one of the most sensual releases of the year. Leo’s lilting vocals in the chorus are absolutely mesmerizing, and only made all the better by Ravi’s contrasting rap verses.

“In the night sky” - AFTER SCHOOL RED 

Debuting in 2011, AFTER SCHOOL RED was the fierce girl-crush juxtaposition to AFTER SCHOOL BLUE’s sweeter concept. Made up of AFTER SCHOOL’s Kahi, Jeong-A, UEE, and Nana, the sub-unit came onto the scene with the single “In the night sky.” Though the song is still definitely on the poppier side, the video turns up the heat both figuratively and literally with the girls partying it up in a desert.