Monster (EP)

It was released on July 6, 2020, by SM Entertainment, with Dreamus serving as the South Korea distributor.

On April 21, 2020, SM Entertainment confirmed that Irene and Seulgi would form Red Velvet's first sub-unit and that the duo was in preparation for their first major release in around June 2020.

[2] The physical release contains two different versions with a CD, a photo booklet, a lyric book and collectibles.

[4] The EP reached 100,000 copies sold on Hanteo in under 3 days, making it the first Red Velvet album to do so.

[5][better source needed] The EP debuted at number five on the Billboard World Album Chart, becoming the duo's top-five entry.