My Sister-In-Law, Luna

by RunicTreetops

Rating: everyone
Tags: Princess Celestia, Slice of Life, Human, Princess Luna, Drama, Anon, My Little Pony: Friendship is Magic, Second Person, Comedy
Length: 2966

Not long ago, you and Celestia were wed. Your lovely wife wants you to get along with her sister, Luna. Your new in-law disagrees.

Life has been pretty terrific since you married the retired Celestia. You've done your best to be the kind of husband that she deserves, but one day, she mentions that you don't really get along with Luna all that well. As such, you decide to rectify that, ready to form a close relationship with your new sister-in-law.

Unfortunately, Luna seems intent on making that difficult for you.

Published 2023-08-05 10:30:01 UTC
Last updated 2023-08-05 10:30:01 UTC

My Sister-In-Law, Luna

"Hey, Luna!"

You call out to the blue mare walking away from you. It's about 11 PM, and the sun set several hours ago. You step out from the doorway and run across the front lawn of the ex-princess's manor in Silver Shoals, just as she crosses the threshold of the property onto the dirt street beyond. She stops when she hears you, turning around to look at you in surprise.

"Anon?"

You skid to a stop as you reach her. There aren't a lot of lights in this part of town, but the clear sky and full moon mean that there is plenty of moonlight to illuminate her face.

"H-hi! I, uh, saw you heading out here and I wondered... hoo..." You have to take a second to catch your breath. "I wondered if you were going on your nightly walk that I've heard so much about."

"...'Heard so much about?' From whom?"

"T-Tia, of course."

"Well, yes, I am about to go for a walk. I don't know what makes it so interesting that it's worth discussing when you're not in my presence, however." Luna glares at you, her gaze piercing your very soul. You feel a tingle crawl down your spine. "Now what did you need?"

You gulp. You have a feeling you're about to get the icy chill of a cold shoulder, but...

"I, uh, I was wondering if I could... you know... join you this evening?"

You give her an anxious smile. She raises an eyebrow at you, looking completely unamused.

"Why?"

"Why? W-well, because... you're my sister-in-law now, and I thought that we could maybe, you know... bond?"

Luna scoffs at you.

"And why would I waste my time trying to bond with someone like you?" You feel your feet run cold. What does she mean by that? "Did my sister put you up to this?!"

"W-well, that's..."

Yes. Yes she did.

"Figures." Luna briefly closes her eyes and sighs, the frustration never leaving her face. "Fine. But only because she'll chew me out tomorrow if I turn you away."

"Th-thank you, Luna. I swear I won't be a burden!"

"I know you won't. Because the second you get on my nerves, you're going to learn what it's like to be sent to the moon."

You feel a cold sweat begin to form on your brow.

"The moon?"

"The moon. I can make up some story to my sister about how you started causing a scene or disturbed the peace or something like that, forcing me to... give you a time out."

"B-but I would never do those things! Tia knows that!"

"Can you honestly say to yourself that she will take your word over her beloved sister's? The sister that still causes her to feel guilt-ridden every time she sees her because she banished said sister to the moon for a thousand years?" You open your mouth to say something, but for some reason, no words come out. "I thought not." Luna turns around and begins to walk away from you, swatting you in the face with her strange, flowing tail as she does so. "Come on, let's get this over with."

It's going to be a long night, isn't it?

You married Celestia just a couple of months ago. The two of you started showing romantic interest in each other back when the royal sisters were still princesses, and their retirement seemed like the perfect excuse for you to start taking things to the next level. Eventually, your relationship finally came to a head, and the two of you lived happily ever after in your little house in Ponyville.

But of course, that's complete bogus. "Happily ever after" doesn't exist. Life goes on, and it doesn't pull any punches.

It was a few days ago now that you and Celestia were sitting at your dining room table, enjoying some leftover fettuccine alfredo that you had made the day before. Things were calm, and the two of you were engaged in some pleasant conversation. However, the tone shifted a little bit when the topic turned towards Luna.

"I was thinking that we should go visit my dear sister this weekend," your lovely wife said.

"Oh yeah, how is she doing over in Silver Shoals? That's a big manor for one pony."

"According to her letters, she is doing just fine. She has always enjoyed relative solitude. She socializes with the locals whenever she is ready, but lively locations tend to wear her out. Hmhm, I attribute that to the fact that she has decided to maintain her nocturnal sleep schedule, but who am I to judge?"

"Well, I'm glad she's going okay. And yeah, a visit would probably be nice. I don't have to work this weekend, so that should be just fine. Do we, uh, need to get there at night to accommodate her sleep schedule?"

"Hmhm, there's no need for that, sunshine. I'll give her a heads-up after dinner. She'll be ready for us. I imagine she'll still stay up late, but she'll get up reasonably early by her own standards to greet us."

"I hope that doesn't inconvenience her too much."

"Nonsense! She's the princess of the moon, and if she can't wake up a bit early, then that's her problem."

"Says the mare that had to wake up before the sunrise every day for the last few thousand years. Literally, 'cause, you know. The sun wouldn't rise until you moved it."

"Haha! You do have a point." She takes another bite of her food before scrunching her nose a little bit and glancing away from you. "By the by, I've been meaning to ask you something."

"Yeah? What's up?"

"Do you... like Luna?"

"Like her? I mean... I guess? We don't really talk all that often. I think we just don't have much in common. Plus, she always acts kind of distant when I'm around."

"You have no idea how many ponies have said that through the years. Look, I know she can seem a bit cold, but she's actually very sweet when you get to know her!"

"Yeah, you, Twilight, and the CMCs have all said as much. It's not like I'm opposed to getting to know her, I just... don't know how to."

"She's your sister now, too, you know."

"Huh. I never really thought about that."

"Here, how about this: Luna always goes for a stroll around town at night, after everypony else has gone to sleep. Why don't you ask to join her? That sounds like it would be a wonderful bonding experience!"

"Uhh, s-sure, I can try that. Maybe it'll even be fun, right?"

"Right!" Tia beams at you with excitement. "Oh, it'll be so nice to have my whole family getting along!"

"What about Cadance? Isn't she your niece?"

"She's your niece now, too."

"Oh. ...Oh. Oh that's weird."

"Yeah that is kind of weird. Let's just not think about it, okay?"

"Good old sister-in-law Luna it is, then."

You walk alongside Luna down the dark dirt road. She doesn't even glance in your direction as you continue past a few street lamps and well-maintained shrubbery. Silver Shoals is a beautiful place. Sucks that you can barely see it in the dark like this.

"So, uh... how do you like Silver Shoals?"

"The ponies here are kind and give me my space. The manor is big enough to accommodate for everything I need, and the local market has more than enough produce to satisfy me. As such, it is sufficient."

Her voice is cold and emotionless. She looks directly in front of her the entire time she speaks, and it feels like you're talking to a robot.

"Well that's... nice... I guess." You look at her for any sign of recognition, finding none. "Er, was it an adjustment moving out of the castle? You don't have any staff to take care of you, or big nighttime responsibilities to take care of, so I imagine it was at least a bit different. It definitely took Tia a few weeks to get used to it."

"Yes, it was an adjustment."

"..."

"..."

"...Is that all?"

"I answered your question, did I not?"

You accidentally let an aggravated sigh slip out and silently hope that she didn't hear it.

"W-well, is there anything you miss about being a princess?"

"My sister."

"Your... what?"

"My sister. Last I checked, she was stolen away from me by some fur-less thing."

"Oh, you're... you're talking about me."

"Indeed."

"Wait, what's wrong with me marrying her?"

You accidentally raised your voice a bit there, but you don't notice. This is far from the first time you've received flak just for being a human, and it's especially not the first time you've done so specifically because Celestia married said human. As a result, it's a bit of a sore subject for you.

"What isn't wrong with you marrying her? Celestia is the most intelligent, most beautiful, most powerful pony to ever exist. What exactly are you compared to that?"

You immediately clam up. She's hitting you right in all of your insecurities. Way to aim below the belt, Luna.

"..."

Try as you might, you just can't bring yourself to say anything in response. You furrow your brow and narrow your eyes in frustration, just as the two of you turn a corner and reach what looks to be a well-lit fountain.

"That's what I thought. Why she chose to marry you is beyond me, but if I had to guess, it's because you're novel."

"I'm... what?"

"She's been around for a long time, human. We both have. We've seen it all, we've done it all. A human suddenly arriving in Equestria is new. It's different. My sister craves different." Luna stops walking once she reaches the base of the fountain and sits on a bench adjacent to it. Considering how angry you are at the moment, you can't bring yourself to sit next to her despite there being ample room to do so. She finally locks eyes with you. "And that's all you are. A novelty. Once that novelty wears off, she's going to discard you like the trash you are."

Her voice is no longer emotionless, instead sounding downright cold and malicious. You've always considered yourself a patient man, but Luna is running that patience very thin.

"I'm doing my best for her."

"I'm sure you are. But your best isn't good enough." Luna presses a hoof to your chest and shoves you backwards, causing you to fall on your butt. "And it never will be." You look at Luna from the ground, at this point having to do everything you can to hold back tears. Slowly, you bring yourself to your feet once more and lock eyes with the alicorn mare. You take a very, very deep breath, but say nothing. "You look like you're about to say something. Go ahead, say it. You know you want to."

In one swift motion, you open your arms wide and shoot forward towards Luna. She flinches as you suddenly wrap your arms around her and pull her into a tight embrace, purposefully squishing her head against your chest.

"Wh-what is the meaning of this?!"

"Thank you for saying all of that, Luna! It's great to finally learn how you feel!" There is an intense level of passive-aggressiveness to your voice. "I'm happy to know that my new sister is willing to be that open with me! What a blessing!"

"H-how DARE you mock me?!"

You squeeze even tighter.

"I'm not mocking you! I'm legitimately relieved to know that you aren't going to pretend to like me just because I'm your brother now!"

To be fair, you aren't lying, but by not bringing up how upset her words made you, you're technically being the bigger man. Right?

To your surprise, Luna suddenly stops struggling. When she does, you decide to put her back down, but as you do, you realize that there is a smile on her face. As you finish placing her back onto the bench, she starts to giggle. Then, she erupts into a fit of laughter.

"Let me guess, it was such a pathetic display that you can't help but laugh at it right? Go on, get it over with."

Luna continues to wheeze with laughter for a few more seconds before you start to hear hoofsteps approaching from behind you. Turning around, you see none other than your wife walking up to the two of you, a concerned look on her face all the while.

"Tia? What are you doing here?"

"I've been following you this whole time." She sighs, looking past you as she does so, her eyes focusing squarely on the still-laughing Luna. "I must apologize to you, sunshine. You've been getting lied to."

"Wh-what?"

Luna finally begins to calm down just enough to speak through her laughing fit.

"OH, OH, haha! Aww, you should have seen the look on your face, Anon! You were all like 'No, I'm not trash!' HAHA! A-and then you were all like 'Luna thinks really highly of her sister, doesn't she?' BWAAAAAHAHAHAHA!"

You've never seen Luna come close to laughing this much. Frankly, you can't help but find it scarier than when she was acting cruel towards you.

"Wait, I don't get it. What's going on?"

Your wife sighs once more before wrapping a wing around you.

"I'm so sorry, dear. I set you up."

"That... doesn't explain anything."

"I... I was curious. I knew you and Luna hadn't spoken much before we got married, and I thought it might be a good idea to... 'test the waters' a bit?"

She grins at you with a look of intense guilt on her face.

"Wait... so all of this was-"

"A lie, yes." Luna interrupts you, having finally stopped laughing but still wearing an amused grin on her face. "Of course I don't think any of that about you, Anon. You're a great guy, and you make my sister happy. That's all that matters to me."

Luna gives you a playful shove on your shoulder, but you fail to react accordingly. There are a million different thoughts going through your head right now.

"For what it's worth, you once again proved that you're the kind, patient man I know you to be. Granted," Celestia continues, "I wasn't expecting Luna to take it so far. Sister, I thought you were going to... I don't know, insult his height or his taste in clothes or something, not his entire identity and sense of self-worth! This was supposed to bring you closer, not drive you further away!"

Your wife raises her voice accusingly at Luna, who immediately goes on the defensive.

"You told me to see how he reacts when I insult him and act like I don't like him! I did exactly as you said!"

"I didn't think I would need to specify that you shouldn't take it that far!"

"Perhaps you shouldn't underestimate your sister in the future, then!"

The two sisters press their noses against each other and glare at one another. You swear that you can see sparks flying between them, but frankly you're still trying to process everything going on.

Unable to decide on what you should be doing or feeling right now, you simply begin to laugh. Should you be mad at Luna for saying all of that? Relieved that she was lying and actually likes you? Angry with Celestia for setting all of this up to begin with and lying to you about it? Happy that she had good intentions? Contemplating the things that were said, regardless of their context? You don't know! Thus, you laugh like a moron.

The two alicorns turn to look at you, confusion on their faces.

"Sunshine?"

"Anon? You okay?"

In a familiar motion, you throw your arms forward, wrapping one arm around the neck of each mare, chuckling as you do so.

"Haha, you two got me good, that's for sure!"

"Y-yeah, we- ugh!"

Luna is cut off as you tighten your grip around their necks a little bit. You aren't actually harming them, but it's more than enough to be super uncomfortable.

"I'm just... so GLAD I get to have a family as wonderful as you two!"

You tighten your grip even further, and they both look at you with concern.

"S-sunshine? What are you-"

"And I just can't WAIT to return the favor!"

One last time, you tighten your grip. Their faces are both pressed uncomfortably against your chest now, their necks craned at awkward, almost painful angles.

"Anon? What do you mean?" Luna asks through forcibly pursed lips.

"It means that you've given me all the motivation I need to act like the little brother I now am."

Luna's eyes widen in horror. Celestia looks at you with an equal amount of fear as she speaks up.

"B-but I'm your wife!"

"Oh, you're going to be paying me back when we get back to the manor." A devious grin makes its way to your face as Celestia's cheeks go red. "Man, I love you two. You're the best!"

The alicorn sisters both laugh nervously. It has been (and will likely continue to be) a turbulent evening. But you know what?

You think this family is going to turn out okay.

"So... I guess you're technically my uncle now, huh?"

Princess Cadance looks at you with a forced smile.

"I guess so."

"..."

"..."

"...Man this is weird."

"Yeah, let's never think about this again."

"Good idea."

And you never did.

Author's Note

I had this idea right before bed and couldn't sleep until it was written.

As always, I appreciate any and all feedback!