It's a clear night, with all the stars visible. I'm just in the process of settling down and relaxing for the next few hours' wait when Sunset hurriedly pulls her head out from the portal and turns to look at me. "It's here!"
"What?" This is my first time seeing her this frantic.
"The Element of Magic! It's in literally the same building as the mirror! And the mirror has been moved to somewhere with even fewer alarms around it than usual, to boot. It's like they're just asking me to take it."
"And you're sure that that's not exactly what they're doing? If your Princess Celestia is anything like Star Swirl was, she knows how to bait some very tempting traps."
That brings Sunset up short. I don't need her flubbing the plan out of excitement now, not when she's this close to getting us both everything we've always wanted.
(And Sonata and Aria, of course. They're still important, even if they've been annoyed with me lately for spending so much of my time with Sunset.)
"Right. Right. That would be just like her, wouldn't it. I can't just go straight there, I need to scry more to make sure there's nothing I'm missing. Go get the fake Element of Magic, while I'm scrying." She turns back to the statue.
"Don't order me around." I clench my fists and don't move from where I'm standing.
Sunset turns back to face me, looking confused for a moment as she processes my response before realization dawns on her face. "Oh. Right. Heh. I guess I'm a bit too focused on this, huh?" She looks down and steps toward me, and as far as I can tell she's genuinely apologetic about her slip-up, but the problem with being in a relationship with someone who I know fully well is a manipulator not too far off my own level is that 'as far as I can tell' isn't necessarily a reliable indicator of genuineness.
Sunset must see something of my thought process on my face, because she goes on. "You know that I'm not just using you, right? Really. You think like me, more than anyp- anybody else I've met, and that's not something I'd ignore just for the sake of another disposable minion."
I nod slowly. "That's... almost convincing. Except I'm pretty sure you could bring out that exact speech even if you really were just using me."
"That's fair." She shuffles awkwardly in place. "How about this? You know that I'm not just using you because I wouldn't need to, for our plans to work. With Flash, I was dating him because he wouldn't have been nearly as useful to me if I hadn't, but you would be helping me anyway, even if we'd stayed purely as allies in world conquest. I spend my time with you beyond that because I want to."
I let out a breath at that. "That's true, isn't it." I step forward to hug her. "I'm more on edge than I'd realized, if I'm missing obvious things like that."
"You?" Sunset sounds vaguely incredulous. "You're never on edge. You're the one who always spends my freakouts calmly asking questions to calm me down. What's wrong?"
"Oh, I'm not on edge about the plan, if that's what you mean." She backs off from the hug enough to watch my face. Wrong instinct, if she wants to catch me lying, but then she is used to spending her time with incompetent high schoolers. "Even if you were to get captured grabbing the Element, it wouldn't be hard for me to go through the portal after you and sing to give you a chance to escape, then leave before anypony could arrange a counterattack." I'm deflecting. I can see on her face that she knows it. I'm not even trying to. Social instincts tuned for interactions with Aria and Sonata and the occasional uninteresting victim don't leave much room for the sorts of admission of emotional vulnerability that keeping up a solid relationship with Sunset entails, here. "The real thing getting to me," I force myself to say, "is what happens after the plan is done. You off ruling Equestria, the three of us dividing up this world, the portal closed. No contact between us except for a few days each year. You... probably don't think like me more than anyone else I've met, because I've lived for a very long time, but you're the most like me of the people I've actually talked to. And it makes spending time with you relaxing in a way that spending time with the others isn't. And that doesn't make me not want to go through with the plan, because it still is fulfilling both of our dreams, but... well. You get it."
"Wait, that's what's been bugging you?" Sunset sounds a lot less sympathetic than I'd expected, which, given her in-fact-convincing case for caring about me, most likely means I'm missing something she thinks is obvious. "I've had a plan for dealing with that since even before we started dating, back when I'd just expected to need to stay in contact with you for diplomatic purposes and stop you from invading my world if you tried to reach too far."
"Oh? What's the plan?"
"Back when I was still Princess Celestia's obedient little student, she gave me a book, magically paired to one of her own. When I wrote in it, the text would appear in her copy too, and the other way around. I haven't touched the thing in years, but I'm planning to leave it with you once I go through. Then I can write to you using Princess Celestia's copy, after I've deposed her. It won't be like being together in person, sure, but it's not 'no contact' either."
"And the paired books work even between here and Equestria?"
"Judging by the messages Princess Celestia sent me in the years immediately after I came here, pleading for me to come back? Yes." A vicious smile works its way onto her face. "All these years, and she's finally going to get her wish tonight. I wonder what she'll think of me now."
I roll my eyes and let her enjoy her little vindictive moment before I respond. "I wish you'd mentioned that plan to me sooner, so I wouldn't have had to waste time worrying about an already-solved problem."
Sunset nods. "I'd have mentioned it if I'd realized you were worrying about it."
"I'll... try to actually let you know, then, next time I'm worrying about something like that."
Sunset comes back in for another hug, and we stand like that for a few moments before separating again. "Anyway," she says. "Could you get the fake Element of Magic for me, while I scry?"
I nod and head into the school.