Girl group Secret Number held their debut showcase in Seoul on May 19.

The five-member multinational group -- Denise, Dita, Jinny, Léa and Soo-dam -- gathered to promote their first single "Who Dis?" Except Soo-dam, the rest were born and raised overseas. They introduced themselves at the showcase, showing off their own charms.

"I am Denise from the U.S. I'm the lead vocalist and the youngest in the group," Denise said. Jinny, who also comes from the U.S., is the rapper of the group. Dita and Léa come from Indonesia and Japan, respectively.

"Who Dis?" is set to be released through major music-streaming sites the same day.