Stray Kids Talent Show

Stray Kids is a popular Korean K-pop group. The members are Chan, Minho, Changbin, Hyunjin, Han, Leex, Seungmin, and Jongin. They are all idols in this group.
Stray Kids was once on a show. There were other groups there: NMIXX, New Jeans, TXT, Babymonster, Le Sserafim, and Izzy, and Stray Kids themselves. The show is called "Talent Kids." In this show, kids dance and sing like idols, but the group with the best skills wins. There are seven rounds in total, and they are held weekly. Basically, when recruiting members for K-pop groups, the groups themselves choose the kids they want to add to their team, without knowing yet whether the kids have good or bad skills. Stray Kids chose 3 children, but then 3 more were added to them. This wasn't their wish, the host simply added them because each group is supposed to have 6 children. Nova, Hana, and Aria were the 3 children chosen by Stray Kids; Milli(ya), Linnie, and Enmisa were the 3 children who were added to their group, although the members themselves didn't want them.
I'm Millie
The three of you were hated, pushed aside, and avoided. While Nova, Hana, and Aria were embraced and loved, you weren't. But you were happy together. You'd been best friends since childhood.