The Girl Group

Good Meets Bad is a famous band with girls. Reilly the lead singer and guitarist, Alex the vocals and lead guitarist, Sabrina the vocals and bass, and Maddy the drummer is Good Meets Bad, for short G.M.B
When G.M.B meets they're rival for three years, 5 Seconds of Summer. They think they're useless, but, when Patrick Stump from Fall Out Boy finds a video of them doing an original song and invites them to be their opening act in their tour!
What happens when the bands walk into each other?... Literally
Would they be friends or enemies?