Forward: Due to the overwhelming levels of snark and general dickishness that Celestia and Mous seem to ooze during every one of their encounters, my 10k Paste hit clop went over really well and got lots of laughs.
For the sake of continuing those good times for reader enjoyment, I've started up this little ditty.
Flanking Maneuvers takes place in the alternate canon that the 10k clop spawned. In this, Celly and Mous became an item before his romance story in BiE began.

With that, enjoy the show.
_________________________________________________________________________________________________________
Flanking Maneuvers, Starring Mous and Celestia.

>You roll over in your bed.
>That goddamn sun has been waking you up every morning since you got here and this was no different.
>You turn over to the other in the bed.
"If I smother you in your sleep, will it never be morning again?"
>Celestia opens her eyes. "If you wanted to not be awake during the day, you should be sleeping with Luna."
"Fuck that. I like my hearing."
>"Then I'm afraid you're going to have to make due, dear." Celestia coos.
>You roll yourself out of bed and walk to the bathroom. 
"You should not raise the sun for me, call it a birthday present."
>"You're birthday present is that I don't send you to the moon for the things you pull."
"You'd miss me."
>You root around the medicine cabinet for your toothbrush.
>You pull out a small tube of medicine.
>Hmm...the spermicide is expired.
"Your anti fetus jelly is good for another month!"
>"How wonderful for you!" Celestia calls back.
>Heh. Dumbass.

>You were sitting at breakfast.
>The entire royal family was here; You, Celestia, Luna, Candace and Shining Armor.
>You mostly sat silently and ate.
>And screwed with Celestia a bit.
"Celly, you burnt my toast."
>"If you would let me off the hook with on this bet, I wouldn't have to use my magic to cook your damn toast."
"Hell no! Then you would learn nothing."
>You bite into the toast.
"And what did you learn?"
>Celestia sighs.
>"That you can make me shout my own name..."
>Heh. 
"You narcissist."
>Luna sighs. "Honestly, I don't see how you to tolerated each other long enough to make it to the altar."
"She fucking tricked me is ho-"
>Celestia shoves a roll in your mouth. "I did no such thing, he simply lost a bet."
>"What sort of bet would be worth you get married over?" Shining Armor asked.
>"A hay sausage eating contest." Celestia said.
>You inhale your roll.
"She still cheated. She can unhinge her jaw or some shit."
>Celestia shoves another roll into your mouth. "Language, dear. We're at breakfast."
>She leans in closer. "Besides, you enjoy my tricks." She whispers.
>I'll show you BREAKfast...
>Cadence eyes the two of you. "That still doesn't explain why the two of you would stay together."
>Celestia straightened her back. "I would be a poor monarch if I attempted to back out on my wor-
>It's your turn to shove a roll of bread into someone's mouth.
"What she means to say is that she likes the feel of my fingers and that I have a wicked long tongue."
>The rest of the royal family just stares at you.
"What? I mean it. Look."
>You open your mouth and take in the shocked reactions as your tongue drops past your chin.
>Gene Simmons can eat it.

>You and Celestia are walking through the castle halls.
"Celly, you and your job make me look like shit."
>"It's your fault for having a shit job."
"Everything is a shit job compared to raising the stupid sun."
>"You work at a spa, dear."
"Don't knock my spa work, you love my spa work."
>"It's still a spa."
"And you still move the second largest celestial body in the solar system!"
>"..."
"..."
>"...Second largest?"
"Your ass is first."
>Celestia takes the offending derriere and shoves it in your face. "I don't hear you complaining."
"Probably because you scream loud enough to raise the bloody dead."
>"I don't hear you complaining about that either." 
"It's just good to know your ancient ass hasn't up and died while I'm stuck inside you."
>You eventually come to a staircase. "This is me." Celestia says.
"Have fun "meeting" the Griffin Jarl."
>Celestia smirks. "What are you implying?"
"That you get more diplomacy done with those lips." You point to her rear. "Then with those." You point to her face.
>Celestia chuckles as she trots up the stairs. "Have a good day at work dear. Learn a new trick with your hands, or I turn you into a statue."
>Yeah, you'd think about that.
>If you were going to work.

>You are Celestia
>You have just spent the better part of the day playing diplomat with the Griffin High Jarl.
>"I think this trade agreement is going to work out, Princess." He says.
"That is very nice to hear Jarl. It is good to see our kingdoms living in harmony.
>"Yes. For far too long have we...been...apart..."
>The Jarl's eyes seem to be watching something behind you.
You sigh. "My husband is making faces again, isn't he?"
>"He appears to be rubbing his buttocks against the window."
>"THE GRAND DUKE OF DOOKY DEMANDS TO KNOW WHY HE WAS NOT INVITED TO THIS DELEGATION!" Mous shouted from outside.
>You turn and cast a spell to blow out the windows.
"Mous, if I've told you once, I've told you a dozen times. You are not a Duke!"
>"I'M FUCKING THE SUN! I CAN BE WHATEVER I WANT!" He says as he jumps off the edge of the window into the moat below.
"AND I REGRET IT EVERY MORNING!" You call down.
>"THAT'S NOT WHAT OUR BEDSHEETS SAY! ALWAYS BET ON THE DUKE!" He shouts back up.
>You grunt and turn back to the Jarl.
>"Should I go?" The Jarl asks.
>"Hell no dude! She's totally checking you out!" Comes a faint voice from outside the window.

>You are Mous.
>You had successfully evaded your wife's wrath.
>You spent the rest of the day following your In-Law Shining Armor as you grilled him about his sex life.
>You snuck back into your room as the sun was getting lowered. "There you are." A voice said from the balcony.
"Aww. Did you miss me? I'm touched."
>"I just thought I'd let you know that the Jarl has agreed to go forward with the trade treaty despite your actions.
"Despite? You mean because of! I just made you look like you have the patience of a saint, Strobe Light. That Jarl is going home knowing that you aren't going to renege on your bargain.
>Celestia laughs as she levitates her jewelry off and takes a seat in front of her mirror.
>"Come brush my hair." She says as you take a drink out of the cooler under the bed.
"With that rat's nest? Don't you have people for that? Or magic?"
>"I do. But I also have a husband with digits."
>You stare at her as she makes a pouty face.
"Fine, but you're making this up to me."
>Celestia rubs the her head against your hand as you grab the brush. "Mmmm~ How?"
"Not like that, you fucking nympho. I want a catapult."
>Celestia releases a mighty laugh. "What could you need a catapult for?"
"Part of this agreement is that you don't ask."
>Another chuckle escapes her. "Have fun pulling it from the South wall."
"Fuck that. "I'll just do stuff with it there." You say as you start to pull the brush through Celestia's stupid moving mane.
>You lift your leg as a fart echoes through the bedroom.
"It was you."