SEE ALSO: Rainbow BLAXX are ready to 'Cha Cha' with new MV teaser

Seung Ah tweeted, "Rainbow BLAXX's unreleased still cuts from the jacket photo shoot!~," along with the above images of her toned and curvy figure in black lingerie. Like their name, the subunit members, Hyunyoung, Jaekyung, Woori, and SeungA, have been seen showing some skin in all-black outfits, following the trend of sexy concepts among girl groups these days.

Get ready to "Cha Cha" with Rainbow BLAXX when they unleash their sexy album on the 20th!