(Yonhap)

Compared to their peers, idol band Red Velvet's ascent to stardom has been a slow burn. The five ladies, who debuted in 2014 under K-pop titan S.M. Entertainment, didn't have a genuine megahit for the first few years while rivals GFriend and TWICE became overnight sensations.

That changed in February 2017 after the success of its catchy pop funk track "Rookie" from the fourth EP album, also titled "Rookie." Last month, Red Velvet dropped another chart-topping number, "Red Flavor," which drove the group to throw its first stand-alone concert since its debut.

"When 'Red Flavor' first came out we were concerned (whether it would be a hit or not). We promoted it hard, emboldened by support of the fans. I'm happy and grateful that the song has played on streaming services for such a long period of time," member Yeri said Sunday at a press conference before the concert at Olympic Park in eastern Seoul.

The concert, titled "Red Room," was initially to run for two days from Friday but, due to strong demand for additional shows, it was extended to three days. The fairy tale-like stage production was built to recreate a room of an ordinary girl.

(Yonhap)

The ladies said they were overwhelmed and emotional after seeing the huge crowd of fans at their show. S.M. Entertainment said the combined audiences for the three-day concert reached 11,000.

"Outside of being greeted by fans at TV stations for music programs, it was the first time for us to see so many fans. We were surprised and even cried, asking ourselves whether they were really all of our fans," said Seulgi.

Joy said the concert was an opportunity to reflect on her past and also renew the fire in her belly.

"After standing on stage, I remembered all the difficulties I had gone through since my trainee days. It had been a while since I gave my all to rehearse and also came to realize the passion inside me," she said.

When asked about future goals, Wendy said, "In the past, I told myself that 'I have to be this or that kind of singer' and tried hard to achieve the goal. But after debuting, being happy and enjoying what I'm doing became the biggest goal for me,"

"If we have ambitious goals but aren't enjoying it, I don't think we can be happy," she added.

Red Velvet is scheduled to perform at Japan's A-Nation concert that will be held at Ajinomoto Stadium in Tokyo on Aug. 26-27. (Yonhap)