Ebony and Ivory?

The picture of Kpop girl group SISTAR's members Dasom and Hyorin while they were shooting
commercial pics was posted on Korea's online community,
and it became the center of attention on the netizens.

Netizens who saw the pic reacted "Ebony and Ivory",
"Hyorin is so sexy in bikinis", "who has a darker skin? VIXX's N or Hyorin?" etc.