Both groups are under SM entertainment,one of the reason why they are called little sister group is that SNSD Jessica is f(x) Krystal kin sister.f(x) debuted 2 years later than SNSD is also a reason .

To f(x),SNSD belongs to what type of group?

On recent interview,f(x) Sulli said "I really respect SNSD sunbaenim and they really taught us a lot of things that benefits us so I'm really very grateful to them". Luna also said "Although SNSD and us are belongs to different type of groups, but to us they are just like sisters whom we known for many years  and they always give us helps whenever we need". 

Krystal then continued "SNSD and f(x) cannot be separate.Even if I'm not able to meet Jessica during their promotions period,but not long ago Jessica send me a message: 'I saw the teaser of your coming album,hope that you girls will get No.1' and she even said that she's going to buy our album, not 1 but 10! ^^".

sidenote// wahhh~~~that's the strong bonding between SNSD and f(x)!
10 albums!!! Jessica unnie really very supportive!
Maybe she get 1 for each member and the other one for her parents ^^
Really hope that f(x) can really make a daebak with their new album, "NU ABO"!!!

Fanstaengoo & snsdlife@snsd-life.blogspot.com