f(x) reveals Krystal's teaser pictures for '4 Walls'

Here's a treat from f(x)'s Krystal who is celebrating her birthday today, October 24!

Beyond gorgeous as always, here are her teaser pictures for f(x)'s 4th album named '4 Walls'~

♥ Preorder f(x)'s 4th album '4 Walls'

♥ More about f(x)'s '4 Walls' here

Credits:
SMEntertainment