The talented ladies of MAMAMOO dropped new solo teaser images for their upcoming April comeback!

As previously teased through a video, the girls will be returning with a special feature, a fifth lady to help with their promotions, but her identity remains a secret!  Although the new teasers still don't reveal the guest member, it has left a great impression that the new promotions will be a bubbly and energetic track perfect for Spring.

The new images show more of the girls' retro-transformation. Rather than the urban sexy divas, MAMAMOO will return with a bubbly pin-up girl concept. Their title song "AHH OOP!" will be a fun, catchy tune everyone can enjoy!

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Which member do you think fits the retro-style the most?