f(x) Amber's new boo? That's got to be Kevin from U-KISS.
Here's their selfie where she playfully expressed, "Hey Eric, i dont need you. I got a new boo now. #asc #kevber"~
Release Date: February 28, 2017
Release Date: January 17, 2017
Release Date: June 28, 2016
Release Date: December 10, 2016