Group Name Unknown
TS entertainment has an upcoming rookie group that is going to debut later this year. No one really know much about it except that one of the members is Bang Yong Guk.
You may recognize him as the guest rapper on Secret’s Song Ji Eun’s song “Going Crazy”
Bang Yong Guk BTS:
TS Ent. released past photos of Bang Yong Guk. He has a lot of past experience in the undergroup hip hop scene. He used to be the maknae of indie crew Soul Connection under the name Jepp Blackman. 
He did an interview for Sports Today: 
‘“When told of his increasing popularity, he shyly laughed and stated, “There are so many people more amazing than me, I’m a bit embarrassed that people have taken an interest. I think that the fans probably felt a sort of freshness in the fact that my husky voice didn’t really match my face.”
Turning to his experience, Bang Yong Guk revealed, “I began performing in Hongdae clubs when I was in my third year of junior high. By the time I was 21 years old, I had performed about 200 times; I gained a lot of experience through that. Now I’m working on writing my own raps, and although my composing skills aren’t up to par yet, I’ve been making my own raps and melodies for a while(laughter).”
Bang Yong Guk actually wrote the haunting rap lyrics for “Going Crazy” himself, and revealed how he came up with them: “I watched a lot of movies and read books on stalking about a month before the song’s release in order to come up with the lyrics. I think I’ve seen nearly all of the movies out there about stalking.”
Bang Yong Guk stated, “I began with the name ‘Jepp Blackman.’ I wanted a name that gave a strong vibe and never once used my real name in my work. Through this opportunity, I thought I’d give my name a try and I’m quite satisfied with it (laughter).”
He continued, “Now that people know me by my real name, I’ve been reminded of the hardships I faced during my younger years. I feel really affectionate towards the name, and as it is pretty unique, I’m glad that people are able to remember it more easily.”
When asked about his plans for his future, he stated, “I’m currently preparing to debut as a five member group. Our debut date isn’t set in stone yet, but luckily I received the opportunity to start promoting first, so I’m going to try my best. I’ll make sure to learn everything I can through this opportunity and pass it on to my members. Instead of focusing on gaining headlines, I think it’s more important to just try my best and work hard (laughter).”’
After Song Ji Eun finished promotions for “Going Crazy” not much was heard from Yong Bang Guk until April 17.
Through his fancafe he uploaded a photo and wrote, “ “I’m rehearsing again after concluding our ‘Going Crazy’promotions. Thank you so much to everyone for supporting me during our activities.”’ 
On April 18, 2011 Bang Yong Guk left an audio message for his fans on TS Ent’s youtube.
Here’s the translation from AllKpop.com
“What’s up, baby! Hello, this is Bang Yong Guk. Yes, nice to see you all! Have you all been well? I’ve just finished promotions for ‘Going Crazy‘ and am focusing on my rehearsals again. I’ve always wanted to thank everyone for the love and support I received during promotions. I’ll work hard to repay the love by becoming a great musician.
Also, please look forward to our five member group! And my fansite, I do monitor it a lot and read all of the comments, so I’ll try to leave more replies when I have time. I hope that you’ll visit often, know what I’m saying?
Anyway, thank you so much, and I love you. One last thing before I go – ‘You, you, you, can’t ever get away from me!’ Bye, let’s meet again.” 
**Last updated April 19, 2011**