MAMAMOO released two teaser images for their upcoming April comeback!

As previously teased through a video, the girls will indeed be returning with a special feature, a fifth lady to help with their promotions this time, but her identity remains a secret! �Who do you think she might be based on the silhouette provided below?

In addition, the girls are deviating from their sexy diva statuses to a more bubbly, retro style with pops of bright colors and funky patterns! �Are you liking what you see? Get super pumped up for the monster rookies' return with "AHH OOP!"

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