Silver woke up and felt disoriented. Looking over himself, he saw he was an alicorn. It wasn't just his larger stature that threw him off, but the blend of magics that made up an alicorn. He marveled at how different it felt from having a single source of power. He reached for his book to try the spell again, only to remember he had cast directly from Fast Change's book and hadn't written it down. "That was silly of me." He rose to his hooves and stretched out, fluttering his bat-like wings.
Somehow, summoned by the sound of those wings alone, Night Watch sailed into the room and landed before Silver. "There you are! And looking good, if I say so myself." She advanced on him and moved to rub noses, which Silver allowed with a smile. She stepped back and pointed at him. "Are you done, or do you need to turn back, again?"
Silver perked his ears. She always knew where the pieces laid. "I was hoping to actually do the date today, but I need two things. Fast Change's spellbook, and Rough Tumble's current location. Then I can go back to being your big lunar prince." He spread his wings for emphasis.
Night Watch snickered softly. "You big oaf. You're always my lunar prince, but, more importantly, you're always mine. Even if you did become an earth pony forever, you wouldn't get rid of me." She waved a wing loosely over Twilight's castle. "Until time itself turns against me, I'm staying at your side."
Silver frowned a little at the image conjured. Would he remain young and vibrant as Night Watch faded away? What an awful thought. Would he watch over that brilliant lunar pony's bed one day... He lowered his head, tears starting to flow as his thoughts turned to death and inevitability. He didn't want that at all, but what fix would there be, what true fix, other than to continue pushing ponies up towards the next level, beyond the grasp of mere time. He thought to Celestia, and how heavy her heart must get, with so many friends fading away over so many years.
A sudden blow woke Silver up. Night Watch had struck him across the snout. "Are you with me? I didn't mean to throw you into an existential crisis. It's flattering that the mere thought of my eventual going would strike you so hard and fast, but we're not there yet." She folded her wings back and ruffled them slightly. "We both have things to do."
Silver forced a nod as the dark thoughts tumbled around. "Sorry, yes. Not today." He leaned in and kissed her forehead. "A world without you is a greatly diminished one. I'm not sure how worthy it would be."
She scowled at him. "And yet, you will go on despite it, because that's what I want you to do, and you wouldn't leave me disappointed like that, now would you?"
Silver lamented at how noble she was being. It felt worse, not better. "Why can't we just save you? Surely you're worth it."
She rolled her eyes. "That's a very nice thought, but my destiny isn't a large one. I'm no warden of dreams. I'm not tender of any celestial bodies. I'm no master of magic itself. I'm just a lunar pony with her head on straight." She thrust a hoof out at him. "And that's enough. Stop demanding the world conform to your whims. That's not healthy, or right. I swear, if you revive me as a zombie, the first thing I'm doing is biting you."
Silver quirked a smile. The thought of a pouty Night Watch zombie, yelling and berating him for necromancy was absurd enough to tickle him. "Alright, no zombies, promise. You'd make a far sexier vampire anyway."
Night paused, then frowned. "Is this a human thing? How is a vampire 'sexy'?"
Silver shrugged. "The same way a lunar pony is, really. They have fangs, and to use it properly, they plunge into your neck and kiss you. They are often seen as symbols of domination and forceful seduction." He ruffled his wings. "You know I wouldn--" He didn't get to finish as Night Watch pounced him and bit deep into his neck. He shuddered and slowly fell back, held in her jaws. It hurt, but her presence was delightful. She nuzzled into him gently as she sank her teeth deeper. He was held captive by her, and he let go to her, surrendering to his toothy overlord.
Night drew back, licking her fangs clean. "We have our own legends of vampires. Terrible creatures of the night. They don't seduce or dominate, they drink until a pony is dead, forever. The 'lucky' ones may wake up as a vampire themselves. Calling a lunar pony a vampire... Those are powerful fighting words, born of fear and mistrust. You're lucky I've grown to understand you a little." She set a hoof on his throat and rubbed gently. "But I wouldn't make that comparison ever again."
Silver rolled over onto his back. "And yet, here I am, satisfied and dominated. We have legends of those kinds of vampires too, mind. Humans are good at making a thousand varieties of each kind of monster. 'Zombie' has been diluted to meaninglessness. We get bored easily, and our storytellers define and redefine these things over and over and over again without concern for what came before. Is it a slow zombie? Is it dropping pieces off as it goes? Stupid, or perhaps cunning like a canny predator? Can it sprint like a cheetah? Some of our zombies do that, and they're all still called zombies."
Night threw up her hooves in annoyance. "Then what's the point of their names? They don't mean anything!"
Silver rolled up and stood. "I can't argue that. People often append the name of the story they're from, or describe them. 'Fast Flaming Zombie', or 'Slow Stupid Zombie' are two very different zombies, and helps get the mental image right. Of course, neither zombie really existed, just stories to entertain foals and bored adults."
Night shook her head. "Well, let me banish that. I've met a zombie before, a real one. I've run into a case where they suspected a vampire too, but they didn't solve that one. They lurk in our night, and they are why the lunar ponies are here to protect the rest of ponykind." She stomped a hoof. "We are the vanguard against the beasts of the night, so, please, don't compare us to them."
She turned away. "Fast Change's currently grounded, but her room's unlocked, so why don't we go borrow a book, hmm?"
Silver began following after Night. "Why isn't she grounded in her room?"
Night spoke over her shoulder, "Twilight wasn't sure she could contain Fast Change so easily, so she made a special cell just for her. Seriously, risking all of Equestria for a rush like that? Not Fast Change's brightest moment. I still love her, mind you, but that was dumb."
Silver nipped at Night's dangling tail, making her pause long enough for him to nuzzle up along it. "Did I mention how much I missed you?"
Night turned to him and rest a hoof on his nose. "Did I mention how much you're not getting away from me again? I don't care what needs doing, I'm going with you, and this now includes Ponyville. Really, I thought you'd be safe from excitement here, and you come back, hypnotized by Pinkie Pie of all things." She tilted her head a little bit. "Come on." She looked over her shoulder. "Was she really that captivating?"
Silver colored through his dark brown fur. "I was blind to her flaws. All I saw was perfection in every little thing she did. I'm glad it's over. When I see your perfection, I know it's no illusion."
Night paused again, then began to walk. "Flatterer."
They arrived at a door and Night fished out a key, easily unlocking the door and pushing inside. "This is her study, where she keeps all her books." She craned her neck in a slow pass, then went for a bookcase. "These were used most recently." She plucked a few off the shelf and offered them. "Find the one, then use it on me."
Silver blinked. "What?"
Night smiled. "Was I not clear? I'm not letting you out of my sight again, my little trouble magnet."
Silver accepted the books in his magic and set them out on the floor before starting to flip through them. "You're alright being an earth pony mare?"
Night tilted her head. "I'll live without wings for a little while, if it keeps you out of trouble. Ponies won't think it's so odd to see two stallions and a mare together anyway. Enough arguing, more reading." She flashed her fanged smile. "You know you want to see it."
Silver looked up at Night and considered her as an earth pony mare. It would be Night Watch, either way. She was more than her species. He found the spell and pulled the book closer. "Alright. I'll start with you, since once I'm changed, no more horn, no more spells. The mare I'm making will be perfectly average, which means you won't need those glasses for a little while."
Night tilted her head. "I hadn't thought about that, I admit." She reached with her wings and snatched the thick glasses, then set them aside before sinking to her belly. "Go on."
Silver focused on her, wrapping her in his magic before he began playing the notes of the transformation. He didn't try to embellish it or improvise. He cast it exactly as it was written, and the magic flared brightly as Night's ears became soft and tuftless. She lost her fangs that he could see when she grunted. Her wings drew in and away, and she became a deep blue earth pony mare. Was this spell set to blue? It seemed to be. "You're still enchanting."
Night shook her head and looked around with blinking eyes. "Everything looks a little different..." She rose to wobbling legs and began walking around. "I feel solid. I guess that's normal."
Silver smiled at her before turning the magic on himself. Playing the same spell without variation, he became Wispy, with his blue fur and silver mane and tail. They looked almost like brother and sister.
Night picked up on this quickly and smiled. "I always wanted a little brother to boss around." She threw a leg over his neck and squeezed him. "Stay by sister. She'll lead you right. Now what name did you take?"
Silver nuzzled her gently. "Wispy Night."
She frowned with thought. "Blue and blonde..." She still had her blond mane and tail, just as Silver had kept his silver ones. "I'll be Wispy Sunset. Wispy and Wispy, brother and sister." She nuzzled him gently. "Sound alright?"
Silver kissed her gently. "It only bothers me that it will look odd if I dip my 'sister' back and kiss her as deeply as I want to right now."
Night held up a hoof. "Save it for Rough Tumble, lover colt. Now, he should be just behind the castle, doing some drills Nefertari set up for him. He won't stop until she tells him to, and I'm fairly certain she won't tell him to until after he collapses, so let's give him a break."