𝐒𝐭𝐚𝐫𝐟𝐚𝐥𝐥: 𝐓𝐡𝐞 𝐓𝐡𝐢𝐫𝐝 𝐒𝐢𝐛𝐥𝐢𝐧𝐠

Chapter 4: Estelle, The Abyss Prince, and Bronya

Aether's POV

"How...How did it get to this point...?" Estelle said, in shock as she stared at the emotionless "abyss prince" that was her so-called older brother. My emotionless look soon faded at the sight of Estelle, and then it turned to fucking shock. "What the..." 'How the hell is she here?! Lumine and I clearly said she stays in that world, so why...why in hell's name is she here now?!' "Estelle. Why in hell's name are you here?" I said, clenching my fists. "You're not supposed to be here! Not at all! You're supposed to leave me alone! You can't just-" 

"Concordia." I heard her say, but it was no longer the sweet and fragile voice from before. No, it was fierce, filled with rage, filled with sadness, filled with despair. "Why would you leave me? Why did you leave us?! Can I not trust you anymore?!" 

"Estelle, you need to understa-" My speech was cut off by the Abyss Herald that stood in front of Estelle. "My prince...She is not human...She has levels of power we cannot understand, truly, I suggest we-" There was a sound of something piercing through metal. I looked down, my eyes widened in shock, as the Abyss Herald had a spear in his chest, and a dark blue liquid, possibly his blood, ejected out of him. "You are no prince, nor are you my brother." Estelle said, deepening her spear in the herald's chest. "I've taken one heart out of someone's chest. I'll do it again." She said, before she looked at me, her eyes filled with rage and coldness.

She just said, so casually, she had committed murder so calmly, and said she'll do it again. I only watched as my expression faltered and the Abyss Herald, who I presumed deceased, fell to the stone ground. Her face was covered in a bit of blood, the hood she wore was as well. "You broke our promise. And now I'll break mine." I didn't understand what she clearly meant, but once I did, I felt like escaping. But I couldn't. My younger sister, yet here she was, getting her "revenge" on me for a promise. 

"Don't you remember our promise? To never separate? When I found out I couldn't contact you, I was worried. But now, I see the path you've taken now. You want to betray me! DON'T YOU?!" She yelled out, her spear was covered in Abyss Herald blood, she was going to do whatever it took to get me back. She was a burning fire of rage currently. 

She didn't calm down at all, instead, I thought she had forfeited at first, because she started walking away. But suddenly, she turned around to face me, and said, "Lumine would be disappointed." I was surprised, in shock, as a yellow portal opened, shaped like a triangle. I slowly stood up from my throne. "Estelle." She didn't...answer me... "Estelle, listen to me." 

"...Goodbye." She said, her back to the portal, as I was still shocked, but guilty. I ran towards her swiftly, trying to reach her. "Estelle. Wait." I said, trying not to yell. But she still stayed silent. She looked...exhausted. I was so close to reaching her, until she just glared at me and stepped in. 

"ESTELLE!" I yelled out to her, but she was already gone. I tried going through the portal too, but I simply went through it. I had truly lost her. Simply, she was gone...

Forever. 

************Nobody's POV************

Aether stood there, feeling guilt, sadness, despair, frustration, all in one. He just lost the only other sibling he was close to, and all because of a stupid promise he remembered making. He actually regretted something, for once. "My prince, is there something wrong, kyu kyu? You seem sad, kyu kyu." An Abyss Mage said. "Kyu Kyu, maybe your sister just despises y-" 

And Aether sent the Mage to rot in hell.

************************

Estelle returned to Mondstadt through the portal. "That wasn't a happy friendly reunion..." The only people she did know other than the siblings who broke their promise to her, was a device she brought from her world called Guardian Unit, but she had named it Bronya, and its official name was "Starbeam." It took the shape of an amber-colored starfish with a blue diamond-shaped gem in the middle, with 6 white wings, 3 on two sides. She always hid it from mortal eyes, and it was like a communication device, Lumine and Aether and everyone on her planet had one.

She was currently at Starsnatch Cliff, looking over the ocean. Bronya was next to her, its wings malfunctioning. "Hm? Starbeam, why are your wings malfunctioning?" "I run on Elemental Energy, remember? Can we just go find a Statue of the Seven and get some power for me? It won't take long." It spoke in a cold and expressive voice.

"Hm. I suppose that the Windrise statue seems to be very powerful, considering the Anemo Archon is always there." Estelle and Bronya go to the large tree from before, under it was the Anemo Statue they were talking about. Estelle watched as Bronya floated over to the statue and took a bit of Anemo Energy from it. "There. That's all I ne-" 

"W-wha..." The two turned around and saw a little kid, like the ones from Mondstadt. They saw Bronya, and then looked scared as fuck. The one rule of having a Guardian Unit was to NEVER show anybody what it was, except the ones who owned one. "What is that?!" The kid exclaimed. 'Shit shit shit-' Estelle thought. Bronya then hid in Estelle's hood and Estelle ran off. "Hey, get back here!"

Estelle was panting as she ran. "Starbeam, please tell me that this is not-" "It's a fake!" Bronya shouted, as Estelle looked back and saw the kid increase in size and turn into a Abyss Mage. "Eh?!" 'Aether must have sent this after me...' "Starbeam. I'll deal with it." 

"But- Sirius-" "Please go, I will not die!" Bronya was scared, but trusted Estelle and said a code, "Transport Starlight." And with that, Bronya disappeared into pixels, somewhere else. Estelle took out her spear and impaled the Abyss Mage to death. "Starbeam, are you okay."

"Yes but....what do I do because there's a group of people approaching me and there's a pixie?"

"....fuck."

********** EXTRA INFO***********

Device (Guardian Unit): Inspired by Mahou Shoujo Lyrical Nanoha ViVid, Vivio's device.

Aether's Guardian Unit: Possibly corrupted due to what Aether is doing.

Lumine's Guardian Unit: Deactivated, can only activate by Lumine, Aether, or Estelle.