Every big band has an origin story, and Roselia is not an exception. In the beginning, it was just Yukina trying to find the perfect members to join her project. Her goal was simple: she wanted to be the lead vocalist of the best band ever, but with such standards, it's difficult to let just anyone join; after all, the members have to be outstanding musicians! Ambitious as she sounds, Yukina was determined to find those people who will work with her to get to a very important festival.

After hearing Sayo perform, Yukina is convinced that she is the guitarist she has been looking for, and so she asks Sayo to join. Turns out, these two have similar personalities, and they quickly discover that they’re both trying to become part of the perfect band. Soon enough, Ako starts following Yukina around, begging her to be the drummer they need. At first, Yukina thinks that Ako is not really serious, but after performing together with Sayo and Lisa, she decides to welcome Ako into the band. Last but not least, it’s Rinko’s turn to join the band. Even though she’s shy and doesn’t know how to interact with people outside video games, Rinko manages to show how serious she is about playing the keyboard. And so, Roselia is finally complete!

Other than because it's awesome, why would anyone want to join a band? The main reason might be to have fun with your friends, but that’s not the case with Roselia. All of its members have a particular reason to be here, and we learn about these reasons throughout the first volume of this manga.

As we mentioned before, Yukina wanted to form a great band to show that music is a serious business. Or so it seems… because in reality, it's daddy issues. She wants to do it for her father, a former musician who had to stop doing music because of some problems with a producer. After that, music has been a forbidden topic at Yukina’s house, but she wants to change that.

Lisa, being Yukina’s childhood friend, only wants to see her smile again, so she’s willing to join the band just to be there for her friend. On the other hand, Sayo was part of a band before joining Roselia, but she felt like something was missing. She wants to prove to her family that she can be good at something and that even though she has a twin sister, she’s still an individual. Sayo resents Hina because she thinks her twin sister is always copying whatever she does. Speaking of sisters, Ako wants to be cool like her older sister, Tomoe, and playing the drums will help her achieve that goal. And Rinko? Well, she just wants to have fun with people and feel like she’s part of something! And something really cool!

Now the band is complete, it’s finally time to start thinking about the first gig. At least, that’s how it should be, except that this band doesn’t have a name yet! With rehearsals and scouting new members, a name for the band wasn’t Yukina’s top priority, but now they need one ASAP. Luckily, when the lead singer finds a flower shop, every piece of this puzzle falls in place, and by combining “rose” and “camelia”, Yukina finds the name for the band: Roselia. And the symbol is, of course, a blue rose... just like the strange flower that called her attention.

With a name and logo, feeling like a real band, the five girls take the stage and perform “Black Shout”, the first of many songs to come. Needless to say, everyone at the live house is impressed by Roselia’s performance!