I found something interesting about this two..

1) I've read somewhere that L and Lizzy are bestfriend - 

and as you guys know , Lizzy and Krystal are bestie

2) Myungsoo are Amber are close to each other

well .... no need to talk about KRYBER --- there are sooooooo many moments about them 

3) Both have y stare

4) Myungsoo Japanese is the best among the group - Krystal can speak a little bit of Japanese (if you watch f(x)'s introduction when they were in Japan and Sulli makes mistake while talking in Japanese, Krystal help her)

5) Myungsoo is the second best at english - Nothing to say about Krystal's english because all of you know she speak english well

6) If Myungsoo weren't an Idol, he want to be a photographer - Krystal loves taking selca

7) Myungsoo seems to speacialize in action role since he know how to fight and use variuos weapons - Krystal really want to be in action movie/drama

8) Both of them seems to be cold but in real life but they're sweet, caring and dorky

9) One of Myungsoo's hobby is rapping - Amber said Krystal is pretty good at rapping and Sulli also said that Krystal wrote a song with Amber for the rap part

10) Bonus