[Brand New Day - Survivable]
They debuted early 2009 and release a few singles in 2009 and were inactive afterwards. Member Soo Ah debuted as a trot singer under the name Geum Dan Bi under a different company. She last released music in 2014 and was a honarary ambassador for the Blue Cross [medicial volunteer organization in Korea] in 2015.
[Dia - Another Boy]
Released a number of singles and collaboration singles from 2009 until 2012. In 2014 she debuted with Kiss&Cry who released two singles before the group went on hiatus after member Hae Na left the company.
[Pink Heart - Shubie]
Debuted under the same agency as Xing. Got into a scandal even before their debut for 'stealing' SNSD's pink heart for their label. Only ever released this single (couldn't find any MV for it). Apparently member Won Hee was filming a movie with a Xing member in 2010 but I couldn't find the movie so maybe it got scrapped. Another member Seo Jin danced with Kahi (After School) on Star King in 2010.
[After School - Ah]
Promoted reguarly until thier last single 2013 'First Love', numerous member changes have occured along the way. Sub-unit Orange Caramel has been more active in recent years. Numerous OMONA members pray for their comeback although signs don't look good.
[Taegoon - Call Me]
Taegoon blew up in 2009 but was stopped promoting by the end of the year. Although an official reason was never released most people assumed he was the person in a blind item about a singer detained on drugs charges in 2010.
[Honey Boys - 4th Hitter]
Only released this single then the two members re-debuted with another member to form the trio ToA (Top of Asia) in 2010. ToA only seemed to have only promoted one single.
[Jumper - Yes]
Only released two singles before disbanding. Member Rocky later debuted with 100% in 2012 under the name Rockhyun. The rapper Dong Min apparently went to the army after the band's disbandment.
[Sori - Red Lips]
Released a few singles in 2009 and 2010. At the end of 2010 she was a guest on Invincible Youth. Her last activity was releasing two singles in 2013.
[Someday - Do You Know]
Sung an OST for Boys over Flowers. Released another single later in 2009 and that's all I could find.
[Haan Yeah Soul - NO.0]
Couldn't find much about her.
[Chung Lim - Step]
He had a few songs in 2009 2010. He was originally an actor but his last project was in 2010~2011.
[NACO - My Girl]
Couldn't find much.
[AJ - Dancing Shoes]
Released one mini album before going onto debut with Beast later in the year.
[Again - 603]
Once again not much info.
[2NE1 - Fire]
I think everyone knows their story...
[Han Una - Mannequin]
Apparently she originally debuted as a actress, that's all I could find.
[Devil & Angel - Bad Girl]
Only ever released this song.
Started on 2009 this time.
Edit: Fixed typos.
Sources: ntxawn69, yein8, 1theK, YGentertainment, KAIIIYO [x], CJENMMUSIC Official, STANFIVE, Priscias, Viatcheslav0,
whinzie, AznJayx3 [x], TOP MEDIA, SagaUn2, xCHELLy, Rola Sato, ahnsaori