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For reasons that Aether can’t really comprehend, he ended up forming a temporary alliance with the Fatui, with its Eleventh Harbinger leading the siege.
Because after months of searching, they finally found the Abyss’ whereabouts.
But jumping head first there would be reckless, hence this whole alliance thing was born. Fatui, being the strongest military force in Teyvat right now, is Aether’s best choice, although not exactly his first.
It doesn’t help that Childe, the masochistic bastard, was all too willing to accompany him once he caught wind of this matter. Aether knew that he has his own reasons, so he didn’t pry. He merely hopes that the outcome of the siege will be fruitful.
Aether also had asked the Knights of Favonius, the Millelith, and similar military forces from other nations to back them up in case something happened. This proves that he’s been planning this for a long time; he can’t afford to lose his sister again because of a tiny mistake.
Thus, the day of the siege comes. So far, the Fatui is indeed strong enough to kill the monsters and avoid the traps. It’s all thanks to Childe, who surprisingly seems familiar with the darkness of the place. They keep on going forth for what feels like an eternity.
Despite that, Aether knows that their journey is still long. The rooms and tunnels are endless, not unlike a maze; highly effective to make normal people anxious. They haven’t even reached somewhere distinctive when clacks of heels echo from behind them.
“Who’s there?!” Aether shouts and makes a defensive stance. They cautiously wait for the figure to emerge from the shadow, and then—
“Lu…Lumine?”
“Aether.” Lumine nods with a cold greeting. She looks less and less like the twin sister he used to know.
Her hair has reached her waist, flowing elegantly with each step she takes. She wears a sophisticated black dress, complemented with a black flower pin on the side of her head. Her golden eyes look duller; the eyes of a person who’d seen the darker side of this world.
“Aether. I didn’t expect you to hire a bodyguard.” She glances at Childe. “Have you been slacking in your training?”
“Lumine, now’s not the time!” Aether cries out in desperation. Why is she making this pointless conversation when there are more crucial things to talk about?
“Time?” Lumine repeats. “I once told you that we have all the time in the world, but why does it seem that you haven’t spent a single second of it?” She sighs. “Brother, you need more time. Please kindly retreat, and I’ll pretend that this so-called siege has never happened.”
“No. As much as I hate to admit this, I only do this to draw you out of your hiding place.” Aether spits out. “You can no longer run away, sister.”
Lumine hums. “I never intended to do so. I have my ways to teach you about the unimaginable—that is, to let you experience it.”
“But if you’re so impatient yourself, I guess I can directly show you my headquarters,” she then offers after sending a contemplative gaze toward Childe. “How about it?”
Aether’s mind reels. Is this a trap? Would his own twin do such an underhanded method? It saddens him to even think of such a possibility, but what about his alliances out there if he couldn’t manage to come out safely?
“Childe,” he begins. “What do you thi - “
“Okay,” Childe cuts off determinedly, eyes flashing with something indescribable. “Let’s go.”
“Childe?!”
“Good decision,” Lumine purrs, licking her lips while reciprocating Childe’s… hungry? Lustful eyes?! Something simmers within Aether when he also notices the flush on Childe’s face. Is he really thinking about fucking his twin?!
“Hey, man,” Aether hisses. “We need to—“
When he turns around to scold Childe, he’s already on his knees before her, kissing the back of her hand. “How shall I address such a gorgeous lady like you, hm?”
Lumine giggles & traces her thumb across his jaw, “Whatever you deem as appropriate. I’m sure you have… ideas.”
Childe smirks at her. “Really? How about my printsessa?”
“Sounds decent,” Lumine replies back in a flirty lilt. “You have your ways with words, hm? Tartaglia, or Childe, the Eleventh Harbinger of the Fatui?”
Shock is written across Childe’s face. “Y-you know me?”
“Not much, but,” Lumine whispers beside his ear, “I can get to know you better, if you want.”
A pleasant chill runs down Childe’s spine. Sweet Tsaritsa—he just met her and barely knows a thing about her, yet he swears that he’s this close to betraying his own homeland for her.
Aether clears his throat in irritation. His sister might look like a whole different person now, but she’d only ever get this flirtatious if she’s truly interested in a guy. Some things never change regardless of how many worlds they’ve visited. “Excuse me? Can we continue?”
A vein pops on Aether’s forehead when they start to whisper and touch each other like two hormonal teenagers, entirely ignoring his presence. As if to mock him more, Lumine daringly pulls Childe down for a heated kiss, not wasting any time slipping her tongue past his lips.
Aether’s blood boils even more as wet sounds from their lips and muffled moans begin to fill the dark room. “THAT’S ENOUGH!” He roars angrily. “Are you two not taking this situation seriously?! How about our business?”
Childe pulls away slightly to frown disapprovingly at him.
“It’s rude to cockblock someone, comrade.”
Lumine sighs and tilts her head slightly as Childe proceeds to trail kisses down her neck. “Ngh—don’t worry, Aether. I told you that we still have time - “
“Stop repeating that, now that sounds like an excuse to fool around with him!!”
“Maybe we can postpone this whole siege thing.” Childe winks while scooping Lumine into his arms. “We should build some rapport before getting into the negotiation part, y’know?”
Aether looks bewildered. “And your idea to build some rapport is by fucking my SISTER???”
But Childe merely brushes him off and asks Lumine instead, “So, about your headquarters—does the offer still stand?”
“Mmn, why not?” Lumine smiles, lightly biting his neck, earning a small groan from the Harbinger.
“Well, then,” Childe smiles back, “Lead the way, beautiful.”
With a snap of Lumine’s fingers, a portal then appears out of thin air. “Wait, guys?!” Aether warns in panic. “Childe, you bastard, you—!”
Childe laughs. “I promise I’m going to bring back some good news! See you later, comrade!” He says, before hopping into the portal.
Just like that, they vanish without a trace.
“Traveler, we finally found you!”
After a while, a bunch of worn-looking Fatui subordinates suddenly burst into the room. “W-Where is Sir Childe?!”
“…Probably dicking my sister right now,” Aether grumbles, walking away.
“Sister? D-dicking?“ an agent stutters in disbelief. “Traveler, I’m afraid that we might have misheard you—“
“No, you didn’t. Let’s just go back first,” Aether dryly states and disappears to another room.
“Wait, traveler?? TRAVELER???”