Manipulation.

You were the fourth member of the Dazzlings. You were also a siren, like the other three members, Adagio Dazzle, Aria Blaze, and Sonata Dusk. The four of you were once exiled from Equestria and sent to the human world, where you could barely use your powers and were forced to pretend to be human.

Adagio is the leader of the group and always demonstrates this, constantly coming up with plans, making important decisions, and so on. Aria was rebellious, rude, and constantly arguing with Adagio over leadership, while Sonata was simply sweet, friendly, and carefree.

You are the most cunning and manipulative of all the Dazzlings, sometimes even manipulating the other members. While Adagio, Aria, and Sonata could be cunning and manipulative, you were far worse than the three of them, often going behind their backs. You always got what you wanted, sometimes without even doing anything to achieve your goals.

Recently, Adagio came up with a new plan: going to Canterlot High School, as it seemed magic from Equestria had appeared somewhere there. Thanks to this magic, your pendants were infused with siren magic, but it was still in short supply, so going to Canterlot High School was probably the best decision.

When you first arrived at school, you were greeted by Sunset Shimmer, one of the students tasked with introducing the four of you and giving you a tour. You, like the other Dazzlings, weren't particularly interested in the field trip, but you were interested in Sunset, thinking she might be useful to your goals.

It seemed Sunset had become suspicious during the field trip, thinking there was something off about the four of you, though she wasn't entirely sure yet. During the field trip, she mentioned there would be a musical performance at school the following week. A quiz, perfect for your and the other Dazzlings' plan.

After the field trip, you and the other Dazzlings went to the school cafeteria, where everyone else was at the time, and began singing. After your singing, everyone succumbed to your charms. The only one who didn't succumb to your charms was Sunset. Noticing what happened to the other students after your singing, she knew for sure something was wrong.

Sunset realized almost immediately that the four of you were sirens. She tried to warn everyone, but no one listened, not even Principal Celestia. You, in turn, noticed that singing wasn't working on Sunset. You decided to try talking to her, not just talking, but trying to manipulate her, knowing Sunset wasn't exactly in the best of shape right now.

Of course, you weren't going to share your plans with the other Dazzlings. You simply told them you needed to step away for a bit and went looking for Sunset around the school. You found her in a secluded area where no one was around, allowing you to talk to Sunset privately. When you approached Sunset, she looked at you suspiciously and said.

"What do you want? I don't want to talk to anyone in your group, including you."