I told you to go right

"Ugh, god, thank fuck this is just sewer water."
"Erm, it doesn't smell like it."
"Please, Luna: I need this."
"Where's Inferno?"
-bloob-
"Fuck, I can't believe you guys agreed to this."
"Neither can I."
"You shut up, you're just me but without the twisted sense of humour."
"-insert dead baby joke here-"
"Ugh, fuck. Wait, there's something brushing against my leg...this better not be a turd."
"Eeeeeenope."
"Then...what is it?"
"It seems to be...~~a severed penis~~ a goat leg."
"Thank god. Anyway, at this next sewage maintenance plant we should stop to get our bearings, resuscitate Inferno, and clean the shit from ourselves."
"Agreed. We could have flown this entire way, but somepony brought three earth ponies along, one of which is wearing behemoth-grade charger armour."
"Your fault for not shouting at me."
"I'd do more than that, you know..."
"Guyyyz, shut up...I'm kin'a droonk herrr..."
"And an alcoholic, might I add."

"Agreed. We stop at this emergency invasion shelter coming up on the left."

2 hours, and several showers later, we'd all decided to just rest here for the night. The shelter, being designed for 'all-out invasion', came with several bunk rooms, a large bathroom, and a living room, kitchens adjacent. Being the seductress that she was, Luna managed to encourage me to go to bed with her, rather than sit with the others in the living room and discuss important things. Unsurprisingly, the blankets were the thinnest ones I'd ever used, but since I was sharing a bed with a large goddess with wings that could encompass two, I knew we'd be fine. I moved in closer to the Princess as another gust of cold air came in through the ventilation shaft.
"Oh, god, you're warm." I whispered. "And soft."
"Just noticed that?" she asked quietly, tightening her wings slightly.
"No, it's just way more noticeable when we're in a sewer bunker designed to defend multiple families against wars that never happened. Plus, the darkness really brings out your eyes."
"I can't really say much, but I do know that your clone has a strange interest in my rump. Think some parts of your mind were put into the clone's more than others?"
"Yep, probably because they're perfect." To demonstrate my point, I moved my right forehoof down and rubbed her wonderful rear, rewarded by a quiet giggle and the embrace tightening.
"Nice." Luna whispered, nibbling my ear for the second time that day. Once again it flickered under her dainty teeth. I heard her chuckle to herself. "Enjoyed that? Let's do the other ear, then..." I secretly enjoyed every single instance of her nibbling my tiny radars. Occasionally, I found that I would shift subconciously, granting the Princess easier access to my opposite ear. Finally, she stopped and gave me time to breath.
"You're so small." she purred.
"You're bigger than me." I replied.

"I bet I can fit you entirely in my wingspan." she laughed. "Go on; curl up into a ball, I'll wrap both of my wings around you." I did as I was asked. Luna's wings loosened slightly, allowing me to bring my legs, wings, and head in so I was small as possible. Then, she tightened her deep blue blanket-like wings, and I could barely move. All I could feel without my hooves was Luna's...oh, YES. "You fell for iiiiiit.~~" she sang. "Now off you go."

"So." I panted. "What do you think your sister and Ebony are doing?"
"I dunno," Luna gasped, both of us breathing heavily and sweating as we lay beside each other. "Sex?"
"Please, don't...not after how tiring that was..." I groaned. "But anypony asks, it was friendly conversation that got heated. Ya?"

"Ya."

The next day, we were woken by the bellowing roar of Terry. I recognised it instantly, as well as Luna, Inferno, Fire, and Thunderlane. Berry was panicking, Big Mac couldn't give a toss.
"What was that?!" she squealed. "M-Monster?!"
"Nope." I grinned, before turning to the dark tunnels ahead. "MORNIN', TERRY!"
"Terry?" Luna laughed. "He's your pet now?"
"No, just an animal we all dislike so much we gave him a name." Inferno cut in. "And if it does get tough with Discord, we can just lure Terramorphous up there to bitch-tentacle-slap him."
"Sounds like a plan." Fire nodded.
"What?! Who's Terramorphous?!" Berry asked quickly.
"Massive worm thing, shoots shards of rock, fires lasers, burrows through the earth, you don't need to know. Anyway; shall we be off?"
"Eeyup." Big Mac smirked, trotting into the sewage below. "Y'all can't beat me at Shit-Wadin'."
"You're on, Big M." Inferno chuckled. The cocky Pegasus promptly disappeared under the murky waters, a stream of bubbles being the only way to know where he was.
"Heh. Eenope.