A/N: I don't own Star vs The Forces of Evil, also this story is set between 'Schools Out' and 'I am Legion'

To kill a Monster

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In the darkness of the castle's dungeon, Marco could sit peacefully in his large oak chair with a wineglass full of fresh blood in his hand and gather his thoughts in the cold silence within this place of torture and misery. Ever since he arrived in Mewni with Star three ago, he had been confined to this dank and sorrowful place until the sun went down where he could travel the castle and be rejoined with his beloved princess. He had been a vampire for nearly three years and in that time frame, his life had changed for what he considered the better.

His parents were more then understanding of his new 'condition' as they called it and still loved him regardless of his bloodlust and wished him the best of luck when he decided to live in Mewni with Star, knowing they couldn't keep the two teens separate. When he was at school, he was no longer called the safe kid, instead he was referred to as the undead kid and was feared throughout the campus and while he never fed on anyone during his school days, he made several bullies and stuck-up girls change schools out of paranoia of being his next meal.

As for his relationship with Star Butterfly, it was never stronger then it was now. Ever since he came to his lover's home world, they had enjoying many different adventures from fighting dragons to harassing Ludo and his men, but there was one thing their combined loved couldn't overcome: Star's parents.

When he first met the king and queen, they only looked upon him with contempt in their eyes before demanding that he thrown back to his world at once and had not for Star's intervention, he would have been forever cut off from the girl he loved. Since then, Marco had attempted over and over again to earn their favor by defending their kingdom, but no matter how many times he saved Mewni from certain destruction, they only saw him as another monster.

But the vampire didn't care whether his lover's parents liked him not, so long as he had Star's heart that was enough for him. She when she would see him at his worst and most feral, she still would kiss him deeply and tell him that everything was alright. With a simple smile, she could stay the cold dead hand of the vampire from butchering someone who had dared to look at her in a way he did not like. With just saying 'I love you' she could calm the most savage of storms he created in his anger. Even if the princess had somehow lost the wand, she would still have the most powerful weapon in the universe to wield: him.

It was getting dark and normally once the sun went down Marco would rise from his coffin, sneak out of his dreary home in the underbelly of the castle and slink his way to Star's room, however he had sensed something unnatural was roaming around on the royal grounds tonight and while he knew Ludo's assassins learned the hard the way to stay away from the princess, that wouldn't stop the height-challenged megalomaniac from sending more food the vampire's way.

But this time it was different, Marco sensed that this newcomer was headed in his direction instead of Star's and awaited his or hers arrival with morbidly dark excitement in his un-beating heart. Soon enough, his visitor entered the dungeon, however rather then come in through the doors; this stranger came into his home by walking through one of the rooms walls.

The person was tall man who was dressed in an all white garb from his white top hat down to his white leather shoes. He wore a clean pressed suite with a red bowtie and a trenchcoat over it that had a red trim to it on the inside with a pair of gloves on each hand. His nose was long and pointy almost like a bird's beak and he had a handlebar mustache that covered his upper lip as well as a monocle over his right eye that had crosshairs engraved into the lens.

But above all else, Marco knew by just the scent off of this man that he was another vampire.

"Hello there my good man!" the newcomer greeted in a friendly manner "I hope I didn't catch you at a bad time?"

"Not at all" Marco replied coolly with a small smirk on his lips "I was just enjoying my drink, would you like some?"

"Oh no thanks, I've already eaten" the fellow vampire said "I'm trying to cut back on heavy drinking anyway"

"Suite yourself" the younger bloodsucker said as he casually swished the blood in the wineglass before taking a quick sniff of it and sip it "ah, thirty-two years old; perfectly aged"

"So you're the great Marco I've heard so much about then?" the stranger asked

"Well I don't know about 'great', but yes I'm Marco" the undead teen answered "And you are who exactly?"

"Oh goodness me where are my manners?" the newcomer spoke in a mock surprised tone of voice "The names Dandy, Daniel Dandy, but I'm better known by my alias"

"And that would be?" Marco questioned further

"The White Death" Daniel replied in now lower more darker tone, trying to sound threatening

"I can see why" the younger vampire acknowledged, trying to stifle a laugh at Dandy's voice as he did "And what is it you do Mr. Dandy?"

"Well I'm glad you asked Marco!" the other vampire began in a now more upbeat manner "As you may have already guessed, I'm a vampire like you, but unlike you I'm in the business of hunting our own kind for the right price"

"A vampire that hunts other vampires? That's just ridiculous if you ask me" Marco questioned the logic in that "Though I must say that you have quite the flare for the dramatics"

"You're the one to talk" Dandy retorted sharply "Have you seen what you're wearing?"

The young vampire looked down at his new attire to try to figure out what the fellow vampire thought was wrong with it. Gone where his jeans and hoodie, they where cast aside for more finer cloths that fit both his new world and his new undead lifestyle. His new outfit consisted of a black petticoat with gold trim to it and a white dress shirt underneath it with white frills coming out of the top of it, a black pair of pants with black dress boots that had silver buckles on them and to top off the whole ensemble, Marco had a long black cape with red trim on the inner lining of it that had a large collar that covered the back of his head.

"This was a gift from the princess" He explained as he looked back up at the slayer "She had it tailor made for me form the finest fabrics in all of Mewni"

"It sounds like the princess truly does care for you" Daniel commented "I wonder, how long will she miss you once you're gone before moving onto someone else?"

Marco didn't answer him; instead he sent a sharp glare to his guest before taking another sip from his wineglass.

"You know your name gets thrown around quite a bit Marco" the undead slayer continued "The things they say…"

Another sip.

"They tell stories of your amazing strength, your remarkable speed and how you guild through oceans of blood" Dandy furthered on "They call you the Prince of Pain. Personally though, I think you're a tad over-hyped"

"Then what are you waiting for?" Marco offered casually as he set his drink down on the small table next to his chair "The first shot's all yours"

"That's all I need" the undead hunter said with a wicked grin on his face

In a flash, Dandy threw open his trenchcoat and revealed to his target this multiple weapons which he used to slay his own kind. He then quickly drew a pair of small crossbows that where armed with sliver-tipped arrows in each hand and proceeded to fire them right into Marco's stomach, striking him in his left shoulder and stomach. To finish the job, Daniel then pulled out a large sliver stake used his superhuman speed to run up to the undead boy and impale him through the chest with it, giving it a good twist in his heart for good measure. Marco let out a pain-hilled hiss before the entire upper half of his body slumped over in his chair.

"Humph, like I said; over-hyped" The White Death scoffed with a smirk

Daniel then made his way toward the wall he had phased through in order to take his leave, but then he heard the sound of a low chuckle behind him. He turned around to see Marco sitting back up in his chair, pulling the arrows out of his body as if they were mere bee stings and dropping them to the ground.

"Is this yours?" he asked as he pulled the stake out of his chest and tossed it aside "You know I'm surprised you even wield sliver at all. It must be because of the gloves"

"H-how is this possible?" the undead hunter stammered out in disbelief

"Did you really think few sliver arrows and a stake are enough to kill me?" Marco asked as he stood up from his seat "I've spent years traveling through different dimensions with Star and in that time I've consumed more then enough blood and souls to survive anything you strike me with!"

As he spoke the air within dungeon seemed to become thick with darkness, making Daniel Dandy begin to feel an emotion he had long since forgotten since he had become a creature of the night: Fear.

"Now I'll show you how real vampires do battle!" the boy declared as his eyes shined red like rubies from hell

The darkness within the room seemed to grow darker then before as the younger vampire readied himself for combat. Marco's hair turned black as it grew down his neck as his muscles expanded to the almost breaking out of his clothing. His claws and fangs drew an inch longer and his skin turned paler until he looked ghost white. A sudden gust of cold eerie wind blew throughout the dungeon, making the vampire's cape to fly open and spread out behind him like a pair of massive wings.

In a panic, Dandy attempted to make his escape through the wall, but before he could take a single step, Marco had already speeded toward him and sliced off his legs with a single swipe of his claws, making him cry out in agony as he fell to the floor.

"What are you?" Dandy demanded "What in the hell are you?!"

"Come on, get up! Attack me!" Marco challenged as he held the other vampire's leg in his hand before crushing it into a bloody paste "You've only suffered the loss of your legs. Summon your familiars! Transform your body! Heal your severed legs and stand! The night is still young and the fun has only just started!"

"Monster! Oh god you're a monster!" the undead hunter cried out in terror

Marco's expression changed from one of pure violence to that of disappointment upon hearing that.

"I see…" he sighed "You're just a sorry excuse for a vampire"

"Shut up! You're nothing but the princess's lapdog!" Dandy shot back in blind rage "you're not even fit to call yourself a vam—"

"Silence!" Marco commanded in powerful demonic voice

If Daniel's heart could still beat, it would be going a mile a second right now.

"So, I'm a dog?" the young vampire asked "Then that makes you dog food"

Marco's body suddenly began to twist and contort into a new and more horrifying new form. His new body was that of a muscular black wolf the size of a bull with flaming red eyes and long fangs that dripped acidic saliva from their tips. With powerful roar, the undead teen lunged at his helpless prey. Daniel Dandy let out one last scream of terror before being devoured whole by the other vampire. After eating his fill of his opponent, Marco returned to his normal self and looked upon the bloody remains of his would-be killer.

"As a vampire you we're nothing more then a piece of shit" he said with disdain as the blood from his enemy began to slither toward him to be absorbed "Now you're just dog shit"

With that, Marco departed from his home. It was time he got some answers as to why someone would be stupid enough to try and have him killed.

King and Queen Butterfly awoke with a start, both awakening from a horrific nightmare that seemed all too real to them and from what they now saw before them; it would seem that the real nightmare had only just begun. In shadows of their darkened room, they could see a pair of red eyes looking coldly back at them.

"Scream and none of your guards will get in here in time to save you" Marco warned them darkly

The vampire then tossed The White Death's top hat unto their bed as way of telling them that he had failed in his mission.

"The next time you send someone to kill me, make sure their worth my time" he informed them

"This wasn't us!" the king defended "It was clearly Ludo who—"

"Spare me your majesty" Marco interrupted sharply "I'm a vampire, not an idiot"

"How did you figure it out?" the queen asked, knowing they where found out

"It wasn't that hard" the princess's lover began "Ludo's assassins only target you two or Star, they never come after me, nor do they have any idea on how to kill a vampire. Plus, when Dandy mentioned how Star would act if I was gone was a dead giveaway as well"

Star's parents glowered at the vampire as he explained their faults to them.

"You're nothing but an unholy monster! Your not worthy of our daughter's love!" the queen scolded "We should have never sent her to your filthy world!"

"I'm going to ignore that out the love I have for Star" Marco sneered "Just like I'm not going to tell her about what happened tonight. Because shockingly enough, she still cares about you even if you two are a pair of old bastards"

The royal parents where caught off guard by his words, they had expected him to jump at the chance at creating a rift between them and Star.

"But I'm warning you both right now: If you do this again, then not even Star will protect you from me" he continued, his eyes flashing brightly to get the point across

And with that, he began to walk backwards towards the wall behind him, keeping his eyes locked on them the whole time.

"Goodnight your majesties" he said with a grin as he seeped through the wall "Don't let the vampires bite"

It was needless to say that neither the king nor queen where going to get any sleep the rest of the night.

"I knew we should've hired that paladin with the bayonets to kill him" the queen told her husband, trying to hide the fear in her voice as she did

As the hours past on, Star began to wonder where Marco was. Usually when the sun went down and the moon rose into the sky, he would already be in room by now, but yet he still did not show. The princess of Mewni had trained herself to stay up in the long hours of the night just to be around the undead boy she called her lover, even though Marco had said time and time again for her to get some sleep, she wouldn't close her eyes for a second unless he laid down with her and waited for her to drift off into her dreams. Tonight the blonde-haired girl kept herself awake by brushing her hair out and putting on her make-up to charm the vampire's affection toward her.

"You know you don't need to wear that stuff to impress me" a voice said casually from behind her

Even though she couldn't see his reflection in the mirror, she already knew who was behind her. Star shot up from her seat and rushed over to Marco, kissing him deeply once she was close enough to him to which he kissed her back with an equal amount of passion. The vampire's cape wrapped around her body as he held her in a loving embrace.

"I'm sorry I'm late babe" he apologized, dropping his 'Dracula speech' as he called it as he did "I lost track of time"

The reason behind Marco's change in tone whenever he was out in public was that at first he thought he could impress her parents, now he just used it to strike terror into the hearts of his enemies, however when it was just him and Star alone, he dropped the monstrous act and went back to the boy she fell in love with.

"Hey, what's this?" the princess asked she wiped off a small trail of blood from the edge of his lip with her thumb "Are you hurt?"

"No, I'm fine" he assured her with a gentle smile "I just had a midnight snack"