Sunset was in Adagio's room, listening to her struggling with a new guitar piece, when they were interrupted by a buzz. Adagio finished the chord sequence she was on before fishing her phone out of her pocket.

She glanced at it, then stared. “Huh,” she said.

“What is it?”

Adagio handed the phone to her. “It's a text from Aria,” she said

Get your butt to the vacant lot on Cedar Road asap. I mean it. NOW.

“That's not ten minutes from here,” said Adagio.

Sunset handed the phone back and climbed to her feet.

The walk was brisk and in silence, save for one comment from Adagio: “I wish you had a motorcycle of something.”

“A motorcycle?”

“You seem the type.”

“Oh.”

The lot's floor was concrete covered with a thin layer of sand and spotted with cracks through which sprouted sickly weeds. Aria stood at the far end, leaning against a graffiti'd wall. She was smirking.

And clinging to her neck was a bright red gem. She extended her hand to reveal two more.

Adagio came to an abrupt halt. “Aria …” she said.

Sunset stopped only momentarily, then left her behind and strode forward.

Aria murmured some sickeningly familiar note, and before she was halfway across the lot, Sunset's legs froze. She tried to step forward again, but they refused to obey.

“Don't be stupid,” said Aria. She turned to Adagio. “She did it! She made sense of those notes after all!”

Sunset craned her neck to look round. Adagio was slowly walking forward. She came to a halt when she was level with Sunset.

“And they're fully charged!” continued Aria. “We're free again. Properly, truly free. We can take this entire continent before we need to feed again! Or we can return to Equestria and take that too!”

When Adagio spoke, her usual tone of command and confidence had dropped from her voice. Quiet, high pitched and almost girlish instead, she said, “Oh … fuck.”

Aria's eyes flicked to Sunset and back again. “You wanted this,” she said. “You gave Sonata those equations.”

“Adagio?” said Sunset.

“I did.” Adagio pursed her lips. “Took pictures of the pages of your notebook. She … she told us she couldn't do anything with them. That was when I …”

Aria had lost her smirk. Now she had a frown verging on being a snarl. “I only called you as a courtesy,” she said. “These will work on any human. If you want to stay, that's fine. I'm sure Trixie would jump at the opportunity.” She looked back at Sunset. “You can take her back with you, anyway. Sunset Shimmer, concubine of Empress Adagio. What do you think?”

Adagio looked at Sunset and put a hand on her shoulder. “Free her,” she ordered Aria.

A brief sung note. Sunset stumbled as feeling came back into her legs. Adagio held her steady.

“You could be on a level with me,” Adagio said. “Have your own palace, your own domain.” Her normal tone crept back into her voice. Her free hand went up to touch her pewter clef necklace.

Sunset studied Adagio's face. It was impossible to read her expression. Except: There seemed to be no trace of warmth in there. A prickly feeling grew behind her eyes.

“No …”

The steady hand on her shoulder shoved backward without warning. Adagio's boot was behind her heel, tripping her. Her outstretched hard didn't stop her from thumping hard on her rear. When she looked up from her scraped, dirty palm, it was through a veil of tears.

Adagio was striding towards Aria, hand outstretched. “Goodbye, little pony,” she said, without looking back. She ripped the necklace off and threw it to the ground.

Behind her a car screeched to a halt. A clatter of opening doors, then voices.

“What in the …” That was Applejack.

Adagio kept walking.

“Aria?” Sonata's voice.

Aria sung another progression.

“What the hell are you doing?” called Rainbow Dash.

Sunset glanced behind her. A Morris Minor – Sonata's car – lay parked at an awkward angle by the road. Applejack and Rainbow Dash flanked Sonata, apparently locked in place like Sunset had been.

Adagio reached Aria, took the gem from her hand, and placed it against her chest. She trembled, eyes closed, like she was caught in some moment of bliss. When it was over, she stood in front of Aria. Her wolfish grin had returned.

“Sonata–” began Aria.

“You opened your present early!” cried Sonata. An accusation in a childish voice. A backwards glance confirmed she hadn't moved.

“Never mind that,” said Aria. “Just get over here. Everything's going to be fine again!”

“Don't,” said Applejack. “Please, Sonata.”

Adagio glanced at Aria. “Let me try,” she said, holding out a hand.

Aria gave her the final gem.

Slowly, Adagio brought it forward and offered it to Sonata.

Then her hand closed around it. She swung round. Her fist came up and connected with Aria's chin. The blow was hard enough to knock her down. Immediately Adagio was kneeling beside her her, reaching down. Aria screamed, a haunting, melancholic sound, as Adagio took the gem from her.

“Little pony! Catch!” Adagio stood and hurled the two gems towards Sunset. She scrambled forward, missed them. The gems thumped against the sand without breaking, and Sunset grabbed them.

Adagio's trembling hand went to her own gem. She closed her eyes as her fingers wrapped around it. A pause, then she pulled. She trembled. Her expression spoke of some great anguish and physical pain. And the gem came away. She threw weakly – the gem landed halfway between her and Sunset, bounced, skittered across the sand – then dropped to her knees and sat heavily on the ground.

Sunset moved forward to grab the final gem. For the briefest of moments, she was entranced by them. She could feel their puissance, magical energy so strong it made the air around them ripple. It could be hers if she wanted it. She swallowed, called to Rainbow Dash, and threw the gems to her. The next moment she was running towards Adagio.

Adagio was on her hands and knees, vomiting. After, she shakily tried to stand. Sunset offered her hand, and Adagio took it. Her face was pale and covered with a thin sheen of sweat. She was still panting, and her knees were trembling.

“Didn't want to hurt you, but …” she said.

Sunset hugged her as tightly as she dared. Behind them, she was vaguely aware of Aria retching. Sonata was beside her.

Adagio began to laugh. “I … I think I just saved the fucking world,” she choked out.

Sunset stroked her hair. “I think you did.” She leaned forward and kissed her.

As they pulled away, Adagio said, “Ugh. Sicky mouth.”

“I know.”

Adagio turned and stared into the distance. “I was hoping our last kiss would be a bit more glamorous.”

“What?”

“We ...” Adagio swallowed. “We just had out true forms ripped away from us. I don't think we're strong enough to survive a second round …”

Sunset froze. She stared at Adagio's pale face. In the background, Sonata held Aria, rocking her gently. She struggled to speak, but no words came out.

Adagio looked into her eyes. Her lips formed a thin smile. “Gotcha,” she said.

“Then …”

“I'll be fine in a few hours.”

“If you hadn't just saved us all, I'd slap you.”

Adagio squeezed her shoulder. “Save it for the bedroom, sweetie.”

Aria was sitting up now, head in her hands. Sonata sat beside her, arm around her, but talking to Rainbow Dash and Applejack.

Sunset looked back to Adagio. “Why did you throw the gems to me?” she said.

“You could have used them.”

“And …?”

“I'm sure you can work it out,” said Adagio.

Sunset looked at her, then pulled her in for a kiss.

“You two might wanna get a room,” said Rainbow Dash, walking over. She paused, pursed her lips, then looked at Adagio. “And I, uh … I guess we were wrong about you.”

“I wouldn't go that far,” said Adagio. She gently moved from Sunset's arms, standing on her own feet, though it still looked as though her knees might give in. “I don't think either of us wanna drag this out. Just – I can't say I'm your friend, Rainbow Dash, but I respect you.” She offered a hand.

Rainbow Dash looked at her for a moment, then shook it. “Deal.”

“And the same goes to you,” said Adagio, walking over towards Applejack, who was still standing beside Aria and Sonata. They too shook hands.

Rainbow Dash brought one of the gems out of the pocket. “I suppose we oughta do something with these?”

“I'll send them back through the portal to Twilight. Best place for them,” said Sunset.

Adagio moved towards Aria – stumbling but regaining her balance – and looked down at her. “Idiot,” she said.

Aria muttered something that sounded like “Fuck off.”

“If we couldn't win when I was in charge, what made you think you had any chance at all?” Adagio sighed and lowered herself to sit beside Aria. And then she reached over and hugged her. Aria didn't respond. For a moment the three former sirens sat in a row together, locked in embrace. When they were finished, Adagio looked up. “Anyone who shares what just happened gets their arms ripped off. You get me?” Silence. “Good.”

Aria and Sonata were whispering to one another, their fingers interlaced.

Adagio tried her to stand. Sunset helped her up.

“I think we need to go home,” said Adagio.

“Good plan.” Sunset kissed her on the cheek.

Author's Notes:

Bit of a change of gears for the last chapter. I'm not, reading back, entirely certain that it works. Oh well. Bonus chapter tomorrow.

(Incidentally, I'm not being very good about edits or replies lately. I apologise. "Life things" have taken precedence.)