With the wish to return to the moon, 4 out of 12 LOONA members signed under Korean entertainment company, MODHAUS after having their contracts terminated after a lengthy legal battle with their ex-company. Heejin, Kim Lip, Jinsoul, and Choerry came together and signed under MODHAUS as members of the project ARTMS in March 2023. ARTMS began as a project under MODHAUS but then evolved into a group. LOONA member, Haseul, later joined the company and ARTMS in June 2023. ODD EYE CIRCLE, an existing subunit composed of members Kim Lip, Jinsoul, and Choerry, redebuted under the ARTMS name on July 12, 2023 with an EP, Version Up. From first debuting as the face of LOONA in 2016, Heejin has begun her solo career yet again with her newest EP, K.

K begins with opener, Kehwa, which paints the landscape of this mini album with its drum and bass beats under her overlaying glitchy vocals. 

The lead single, Algorithm, takes inspiration from artists who shaped the ‘80s western pop sound like Madonna, Janet Jackson, and Cyndi Lauper. Whilst the majority of K-pop groups are taking inspiration from the early 2000’s, Heejin goes back to the 1980’s. The track utilizes 198​​0’s bass and cascading synths, and includes her fun vocals to stand out on the track. Heejin is also co-credited for the lyrics on every track on the album. Visually, the music video showcases Korean traditional beauty and past historical periods, as well as featuring the other 4 ARTMS members as a special cameo. 

Sad Girls Club is a slower, moodier R&B pop track that continues the use of synth work in the background and showcases her gentle vocals. Video Game is an addictive track where Heejin’s vocals truly shine that goes by quickly. Nokia is another slower, more acoustic track that shows more of her lovely vocals. Addiction is Song G from TripleS’ quarterfinal gravity event, where fans of the group can vote for songs for the group to sing later. TripleS is MODHAUS’ first project group, where the group will have 24 members and primarily works in smaller, rotational units voted on by fans. Addiction is a poppy R&B track that stacks Heejin’s vocals and closes the album on a rather positive note.

K by Heejin is a strong, cohesive, vibey album that not only shows off her beautiful vocals but  shows off her growing potential as a soloist and songwriter as well.