«Monster» is the debut EP by Red Velvet’s members “Irene & Seulgi». They are the first sub-unit of South Korean girl group Red Velvet.

The EP was released on July 6, 2020 by SM Entertainment, with Dreamus serving as the South Korea distributor.
The EP contains six tracks, including the title track and the follow-up single “Naughty” which is currently available on the physical edition only.

EKKO’s hitmakers have produced and co-written the following songs:
1. Monster (co-written by Kenzie)
2. Naughty (produced and co-written by Moonshine and Charite)
3. Feel Good (produced and co-written by Moonshine, Tania Doko, Maribelle Joyce Anes)
4. Diamond (co-written by Kim Yeon-seo)
5. Jelly (produced and co-written by minGtion, Andrew Choi, Kim Yeon-seo)
6. Uncover (co-written by Kim Yeon-seo)