f(x)'s member Amber revealed a picture with Girls' Generation's Taeyeon and Super Junior's Heechul.

"Blonde 3x, the yellow hair team," posted Amber on her Instagram on Monday along with a picture.

In the picture, Amber, Taeyeon, and Heechul are posing for the camera together. All three of them have blonde hair and are making funny faces at the camera, revealing their close friendship.

The three had attended SM Town Live World Tour Japan Special Edition concert on this day.