I'm keeping watch outside the portal, waiting for Sunset to either come back or stay gone for long enough that it's time to go in myself and rescue her, when a bus pulls up in front of the school. I don't know what a bus is doing here in the middle of the night, but by the sound of it, it's filled with teenagers, so I can only assume there's some sort of school event happening that Sunset wasn't aware of.
If the other two Sirens were here, it would be an easy situation to resolve. Sing until the teenagers are too busy fighting each other to worry about the fact that three girls they don't recognize are loitering around the grotesque horse statue, and enjoy a nice meal while we wait for Sunset. But they're not here. It's just me. For all that I've been alone with Sunset pretty often lately, I'm not used to the other two not being around when it comes time to execute a plan. By myself, on this magic-choked garbage dump of a world, I doubt I can get even half the group distracted fighting each other, never mind the actually-strong-willed ones.
If I can't use brute force, the next-best approach is persuasion. I step out from behind the statue and make a beeline for the blue-skinned adult who seems to be leading whatever this is. "Excuse me," I say, putting on my best Trustworthy Smile.
It takes a moment for her to give me any attention, amid her efforts at ensuring that the teenagers are all off the bus and grouped together, but eventually she does. "Sorry about that. Yes?"
"I just wanted to check in, and make sure that I won't be in the way of your event if I sit under the horse statue and sing to myself. I don't go here, obviously, but this is my favorite place to relax at night, and I'm hoping I'll still be able to stay here despite whatever event you're holding right now?"
"That should be fine, yes," she says. "We will be out here only briefly, and the school building is soundproofed well. I very much doubt your singing will prove any disruption to us."
There's a clinking sound from the direction of the portal, but a quick glance shows no sign of Sunset, only some miscellaneous wandering students, one bending over to pick something up.
"Thank you," I tell her, and return to my vigil next to the portal. The yellow girl who picked up whatever made the clanging noise walks past me towards the woman I was just talking to.
Just a moment later, Sunset herself comes back through, looking slightly tired but far more satisfied than frustrated. She ran into trouble but managed to get the Element anyway, then.
Sunset briefly glances around the ground around the portal, then at the students standing nearby (none of whom saw the moment of her appearance, fortunately), before turning to me. "Do you have the Element?"
"Me? How could I have gotten..." I put the pieces together. "The yellow girl. That's what she was picking up." Sunset ran into trouble. Of course. Throw the Element through the portal at the first chance, to put it out of her pursuers' easy reach and to alert me that something is wrong. Except I wasn't at the portal. I was busy negotiating with the blue woman. Which meant...
I point Sunset in the direction of the pair of them, now standing together and talking, and then I start singing. I don't have any ability to harmonize vocals, being on my own like this, but if I'm lucky my voice will still be enough to drive the two into a fight and open a chance for me or Sunset to grab the Element. I sing about how mysteries can be dangerous, about how it's best to pass unfamiliar problems off to others who can take the brunt of the risk rather than facing it oneself. I permeate the song with imagery of enchanted or cursed jewelery from throughout this world's mythology.
The two of them seem at least mildly entranced by my voice, enough to watch our approach, although not enough to stop whatever conversation they're having. But the blue one, who's now holding the crown, shows no sign of an impulse to push it off onto anyone else. She just starts walking with it to the school building, and—
And I've been an idiot. Of course she doesn't have any urge to pass it off; she thinks it's the perfectly familiar crown from the Fall Whatever Dance, not a mysterious unknown bit of jewelery. I should have anticipated that, and found some other angle instead. That was an Aria-tier mistake, which means the stress of the night has gotten to me more than I'd realized. But it's going to be hard to pivot my song convincingly at this point, especially when my target has already shaken off her enchantment and walked off. I wave Sunset forward, instead, hoping that her familiarity with the school and its staff will let her win out where I failed.
But, after a few moments of discussion with the blue woman, Sunset comes back to me, looking frustrated. "Luna is locking the crown away until the Fall Formal. Looks like we're putting the plan on hold for two days, while I crush the competition here for the last time."