For fans who attended one of MAMAMOO's 'MOOSICAL' concerts, this won't come as too much of a surprise, but other fans will be overjoyed at the bomb the group dropped just now!

SEE ALSO: Super Junior's Ryeowook claps back at a malicious commenter claiming to be a fan

The talented girl group will be releasing a sub-unit comprised of the rapper line, Moon Byul and Hwa Sa!  The song will be called "Dab Dab," which translates to "frustrating," and it will be dropped on August 31.  The song has already been revealed during their concert, but fans can relive it through the August 31 midnight release!

But wait, there's more!  Check out the other sub-unit here.