Disclaimer- I don't own BTVS, Harry Potter or Supernatural.

"Speaking"

Thoughts

'Leglimency/Telepathy'

"Spells"

"Foreign Languages"

"How the hell did I get here?" Sirius Orion Black wondered aloud.

He took in his surroundings. By the cars and the houses he was in a muggle neighborhood. By the warmth he also knew he definitely wasn't in England. The last thing he remembered was fighting Bella in the Department of Mysteries. He had been hit by a spell when he, admittedly, had been playing around with her and had been knocked backwards.

Harry screaming his name had tore at his heart but then everything had gone black. Then he had woken up here, standing up. Stretching he relished in the feeling of absolutely no pain in his body. Even after his treatment he had some lingering joint pain and nightmares. Stretching out with his senses he grimaced with disgust. The surroundings felt darker than anything he had ever felt outside of Azkaban. Hell it might even worse. It was even worse than Grimmauld Place and all the dark magic the house had soaked up over the years.

Scratching his forehead he tried to remember the charm that would tell him where he was.

"Fornar Dubreai." Sirius cast causing coordinates to pop out of his wand. "I'm in the States? How the hell did I get to the Western United States?"

Seeing a little demon jump at him he shook his head before he quickly banished it in another direction. As soon as he did he saw a whole other pack of them barreling down the street towards him. Waving his wand he erected a wall of flame between him and themselves causing them to scream and screech in anger. Raising his wand to incinerate them he was stopped by a shout.

"Stop! Don't hurt them!" A frantic young, female voice called out.

Whirling around Sirius kept his wand pointed ahead but slightly to the ground, ready but not quite pointing towards a target. Sirius almost wolf-whistled. The red haired teenager wasn't a bad looking bird at all, especially with the outfit she was wearing. What? He was in his thirties, not dead. Besides while he wouldn't dip his wand into a teenager that didn't mean he couldn't look and admire a fine piece of ass.

"Who are my lady?" Sirius asked, giving her a suave smile.

A confused look came to the redhead's face.

"Xander it's me." The ghost said. "Willow?"

"I am afraid that you have me confused with someone else." Sirius told her. "I am Sirius Black."

"Where the bloody hell am I?" Sirius asked. "I have rarely felt somewhere so bloody evil."

"Sunnydale, California." Willow replied before continuing at Sirius' blank look. "The Hellmouth."

Sirius had a dumbfounded look his face before he cursed up a blue streak. He was on Tiamat's Maw, as it was known in Europe. A little crack in the dimensional wall between theirs and several hell dimensions. Just bloody fantastic. Most wizards, at least the intelligent ones, avoided a Hellmouth like a plague.

There were seven known Hellmouths in the world. Three in the United States. Sunnydale, Cleveland and Rhode Island. One in Europe in Italy. One in Egypt, one in Chile and one in Australia.

The places were darker than any other place on Earth. They exuded malevolence and attracted demons and other monsters. Sure witches and wizards could deal with many demons with their magic. However there were those who were immune to magic and those who were more powerful Sorcerers than the average witch or wizard. Most witches and wizards couldn't stand the feel of a Hellmouth and it could have negative effects on their magic.

Seeing another group running towards them he swept his wand in the air towards them. A wave of red light erupted from his wand, knocking the monsters unconscious. The ghost jumped in front of him with her arms spread wide and a glare on her face.

"I told you not to hurt them!" Willow yelled at him.

"Calm down girl I merely stunned them." Sirius snapped in irritation. "They will wake up on their own in about an hour completely unharmed. Now can you explain what's going on?"

The ghost huffed at him but explained.

"I think we've all turned into our costumes." Willow informed him. "It's Halloween and everyone is dressed up. I dressed up as a ghost and Xander dressed up as a wizard. Our friend Buffy dressed up as a noble woman from the seventeen hundreds."

"A ghost of what?" Sirius asked, raising a brow at her short skirt and belly shirt

The ghost flushed and crossed her arms over herself.

"Buffy gave me these clothes!" She snapped. "I was wearing a sheet over them."

"A sheet?" Sirius asked confused before shook his head when he got it. "Oh now I remember. Lily said muggle ghost costumes are made of sheets. Silly buggers."

A loud scream interrupted them.

"Buffy!" Willow screamed as she took off.

Here we go again. Sirius thought as he started following her.

-0-0-0-0-0-0-

Sirius and Willow had gone to collect the ghost's friend Buffy after she screamed. He had a hard time thinking of the air-headed blond bint as a Slayer but son of House Black decided to give her the benefit of the doubt with the spell effecting her. The house was a modest two story house that had a happy and well loved feel that Grimmauld Place had never had.

"Mrs. Summer?" Willow called out but there was no answer. She waved Sirius inside. "She must be gone."

Sirius levitated the unconscious blond inside and laid her out on the couch. Looking around Sirius decided liked the house even if none of the pictures moved. Peering closer at the pictures Sirius could see the boy who he was possessing, the red haired ghost, the blond girl and a woman who clearly her mother. Sirius whistled to himself. Now there was a bird he definitely wouldn't kick out of his bed.

Willow glared at him as if hearing his thoughts causing him to grin and shrug at her. She huffed before she turned her back to him. Walking around Sirius waved his wand setting up an intent ward. It wouldn't last very long without being anchored to a ward stone but it should be enough. Waving his wand at the door he conjured several more locks on it and nailed several boards to it. He finished by sealing it magically.

Hearing a scream from outside Sirius' grip on his wand tightened.

"Oh come on!" Sirius moaned.

He had just gotten the house locked up. Sighing he waved it at the door causing the locks and boards he had conjured to disappear before the door flung itself open.

"Be careful!" Willow told him worried.

"Don't worry I will be." Sirius said, flashing her a smile and flicking on the porch light.

Rushing outside he saw a beautiful teenage bird with long brown hair running away from a large hairy Sasquatch creature. Actually having seen an American Sasquatch he knew that it wasn't a real one. It must have been some chump turned into their costume.

"Quick get inside!" Sirius yelled at the girl causing her face to light up in relief.

A jet of a light flew past her causing the Sasquatch to trip just as the girl made her way behind him. The Sasquatch pushed itself off the ground with a look of anger.

"I think you should leaving mate." Sirius told it, wand pointed at it firmly.

The Sasquatch slammed it's fists into it's chest several times with a roar.

"Don't say I didn't warn you mate." Sirius drawled before he hit with it charm that plucked out every hair on it's body. Every Single One. At Once. Painfully! The angry roar turned into a scream of pain. Deciding it had enough when Sirius raised his wand further it whined as it ran away, now completely bald and naked.

"Since when can you do magic Doofus?" The girl snapped at him.

"Why don't you settle down Kitten and let the mature ones deal with this." Sirius drawled.

"Oh!" The girl screamed in frustration, her face turning red. "Don't tell me what to do!"

The ghostly Willow stepped in between them before Sirius could say anything back.

"Wait Cordelia you're not really a cat!" Willow informed.

The girl, apparently Cordelia, shot Willow a look like she was nuts.

"Duh!" Cordelia scoffed. "What are you on loser?"

"Wait you didn't turn into your costume?" Sirius asked.

"What are you talking about?" Cordelia asked with a glare.

"Everyone else we've met has turned into their costumes." Willow explained to her. "Xander is some wizard named Sirius Black and Buffy turned into a noble woman."

"Another lose woman?" Buffy asked, having woken up causing the others to jump.

Cordelia turned her dark look on her.

"What did you call me?" Cordelia ground out through her teeth.

"A slag, a woman of the night?" Buffy glared back at her before sneering at Sirius. "What proper man would be seen in your company?"

"Cordelia why don't you go checkout the upstairs." Willow told her.

"Here." Sirius said, waving his wand a conjuring a wooden bat for her.

"Magic!" The Noblewoman screamed in fear, crossing herself. "Devil worshipper!"

"Thanks." Cordelia said reluctantly as he took the bat.

"Why don't you go back to sleep." Sirius suggested to Buffy hitting with a light sleeping charm.

Willow shot him a withering look.

"What?" Sirius asked at the look. "She's annoying and has been no help."

A ping on his intent ward had Sirius whirling around towards the kitchen. He blinked at what he sensed. A tall pale skinned figure with a somewhat attractive face stepped into the room.

Vampire! His senses screamed. It took him several seconds to recognize the beast. It had been a long time since Defense Against the Dark Arts. The Revnant vampire was Angelus, the Scourge of Europe. A serious monster in his time. He had disappeared for decades and apparently had come to the States.

"Buffy, Willow I'm glad you're alright!" The vampire said. "It's chaos out there."

"What are you doing here Angelus?" Sirius spat, his wand pointed at the vampire.

"What? Xander? Why are you pointing a wand at me?" The demon asked incredulously. "How do you even have a wand?"

"It seems that I am possessing this Alexander Harris." Sirius drawled. "My name is Sirius Orion Black. Head of the Ancient and Most Noble House of Black. You may address me as Lord Black."

Angel somehow paled even further. Even he had heard of the Ancient and Most Noble House of Black having been a squib. They were darkest and most vicious House in Wizarding Britain and one of the runner ups in Europe. They never forgot a slight and never let those who challenged them to get away.

Their revenge and plots had sent the shivers down many a back, even dark wizards. Dark Lords were wary of challenging them. Famous for producing powerful witches and wizards, dark witches and wizards, with many magical talents. A lot of the time they were quite insane but also didn't suffer trespasses against them.

"Wait!" Willow urged Sirius, stepping in front of him causing him to adjust his aim. "Don't hurt him!"

"That a vampire Willow." Sirius glared at her. "It will do it's best to kill everyone here. Do you want that on your conscience?"

"He's a good vampire!" Willow argued.

"There's no such thing as a good Revnant vampire." Sirius argued. "Get out of the way."

"I was cursed." The vampire spoke up a look of remorse on his face. "D-Darla, the others and I attacked a Gypsy tribe. I killed their favorite daughter, a seer. They cursed me with my human soul. I remembered everything I had ever done and I-I hated it. It tore at me, it still does. They wanted the demon tormented and I am tormented alongside it. I chose the name Angel and fled from Europe."

"You'll excused me if I don't just take your word for it." Sirius narrowed his eyes at him.

Angel grimaced but nodded.

"Check." He said curtly.

Sirius cast several spells on him before he stopped. Sirius almost whistled. That was high level magic. Soul Magic was forbidden by most magical Ministries and considered to be Black Magic. Most would be executed for using it.

"Fine." Sirius snapped. "I will trust you for now but I will be keeping an eye on you."

"I-I'm going to go and check in with Giles." Willow said. "Hopefully he will know what is going on."

Sirius nodded begrudgingly.

"He's a Watcher." Sirius said. "He might be able to help."

Willow quickly flew away out the side of house leaving Sirius alone with the other two.

"The upstairs looks alright." Cordelia said as she came down the stairs. Seeing Angel a smile came to her face. "Well hello."

Sirius nearly gagged as he heard her flirt with the Revnant.

"He's a vampire." Sirius informed her in amusement, watching her face screw up in disgust.

"What?" She asked backing up in surprise.

"You're flirting with a vampire." Sirius said.

"Oh god." Cordelia gagged before she glared at Sirius. "Why aren't you roasting him?"

"He has a soul and apparently helps the Slayer." Sirius informed her. It was clear that he wasn't completely happy with the situation. Cordelia moved across the room to stand beside him, all the while eyeing Angel.

The front window broke as a rock flew through it before the lights cut out. Stepping forward Sirius eyed the outside. There were several demons and a pack of vampires approaching the house.

"Come out and some of you may be spared!" A cockney accent yelled. A bleach blond vampire stepped forward.

"Spike!" Angel spat from beside him.

"William the Bloody?" Sirius asked him.

Angel nodded causing Sirius to curse slightly.

The killer of two Vampire Slayers and a vampire who loved torturing his victims with railway spikes.

"Nobody will be surrendering Spike!" Angel yelled. "Leave while you still can."

"I don't think so poofter." Spike yelled back before he gestured towards his minions.

Sirius seeing them rushing towards the house conjured a wall of fire to cover the front yard. A couple of vampires screamed as they didn't stop in time and erupted in flames. Sirius and Angel ducked as several shots were fired at the house from guns.

"Now this is my type of fight!" Sirius yelled. His wand spat out several fireballs, one of which caught a nearby vehicle causing it to explode. Sirius laughed. Dark curses and fire leapt from his wand killing demons and vampires alike. Snapping his fingers Sirius caused several vampires to disappear in a pillar of black flames. The Black Flames, Black family magic. It twisted like a living serpent under his command and consumed several other vampires before pouncing on a line of vehicles causing to erupt and cut off the demon's retreat.

"Buffy's gone!" Cordelia yelled just as Sirius saw her being dragged towards Spike.

"Stupid bint!" Sirius cursed. Sirius was really getting exasperated with the Slayer. First she had run away and now she had gotten herself captured by a vampire who actually wanted to kill her.

"What are you going to do now you wanker?" The vampire asked him mockingly.

"Oh I don't know." Sirius sneered. "This!"

He knew just the spell to use for the leeches to. Shoving Angel down to the floor he unleashed the spell. Lumos Solem while mostly used as a source of very bright light had originally been designed to be used against vampires by mimicking the properties of sunlight. Bright sunlight issued from his wand causing the vampire to jump backwards with a screech, it's face burnt and it's body smoking as it tried to cover itself. Several of it's minions weren't as lucky as they burnt up with a scream leaving behind only ash covered clothes. Suddenly Sirius felt a shudder go through him before darkness took him again.

"Oh! What happened?" Xander said looking around in surprise before he passed out.

Xander came to in foggy surroundings. Pushing himself to his feet he stumbled as his surroundings turned into an old fashioned pub. Sitting at one of the tables was someone he recognized. Sirius Orion Black looking younger and a lot healthier than he had the last time the wizard looked in a mirror. He also looked happier and unburdened.

"Hello Alexander." Sirius Black said with a small smile.

"Um. Hello." Xander said nervously. "What am I doing here?"

Looking around he asked another question.

"Where am I anyway?"

"This is a meeting place for the living."

Sirius pointed at Xander.

"And the dead."

He pointed at himself.

"As for why you are here, well that's more complicated." Sirius said with a sigh, rubbing a hand down his face. "On Halloween you dressed yourself as a wizard. Ethan Rayne, a Chaos Mage, cast a spell turning you into your costume. In life I was a follow of Loki, the Norse God of Magic and Trickery. He pulled a favor with Janus for me and you became me. I – I well I'll just come out and say it...I'm your father kid."

Xander blinked in surprise before shaking his head.

"I think you have me confused with someone else." Xander told him. "As much as I wish otherwise Tony Harris is my father."

Sirius shook his head.

"No Xander I am your father." Sirius pushed on despite his protest. "I and your mother, um,"

He glanced at Xander before clearing his throat.

"Got together when I was nineteen when my friends and I were visiting the States. She was a muggleborn witch and my father found out she was pregnant. He was furious and he cursed your mother with a spell that bound her magic and caused you to be born with your magic locked, basically making you a squib. He then obliviated me. Unfortunately I never remembered that I was a father before I died. When you die any mental manipulation is removed."

A blank part on the wall started playing memories of Sirius' time with his a girl he recognized as a younger version of his mother. Luckily for him it didn't show any intimate moments between them. There were things about his mother he just didn't need to know. Xander even saw the fight between Sirius and his father before he saw Sirius being obliviated. A dark look crossed Sirius' face before he shook his head.

"Do you believe me now?" He asked.

Xander nodded slowly.

"Okay – " Xander began, his heart beating harder. "What does this mean for me?"

"You are my son and heir." Sirius explained. "Last night broke the curse on you allowing your magical core to wake up. Congratulations you're a wizard!"

"What? But magic always messes up around me." Xander protested, shaking his head. "I can't be a wizard."

Sirius chuckled.

"That was the curse at work Xander." Sirius pointed out. "Without the curse your magic is going to be free. You will need training. I am going to offer you my memories to give you a leg up. You won't get the emotional aspect but will get the knowledge. All that will be left out is my time spent in Azkaban."

"Thank you." Xander said.

Sirius gripped his shoulder.

"Don't worry kid. You are my son. It's the least I could do for not being able to be there for you over the years." Sirius told him, tears gathering in his eyes before he blinked them away with a deep sniff. "My Will was also altered so you have an inheritance coming your way. Half the Black family fortune plus artifacts and my enchanted Royal Enfield. Gods I loved that thing."

Sirius cleared his throat before continuing.

"I also left you the majority of the Black Family Properties. The only one I didn't you will know why. You will also inherit the title of Lord Black, our seat on the Wizengamot and the Board of Governors but you don't have to sit for them if you don't want to. A vault has been set up for you in Thasura, a bank ran by Dwarves. The are a lot more friendly than goblins and offer better service as well. There is also another vault left to me by my Uncle Alphard in Gringotts New York. I took some of it out for myself when I inherited it but the rest of it has sat there gathering interest and receiving the earnings from Uncle Alphard's plantations and farm."

Xander eyes widened as he the area around them shuddered.

"What happening?"

"You are in a coma right now while your magic fixes us the damages Tony Harris did and not to mention the residue and effects from living on Tiamat's Maw." Sirius informed him seriously. "You're going to be alright and are getting the help you need. I suggest you ask for a talent test as well from Thasura. You need to know about any gifts you have."

Sirius got up and dragged him into a hug. It was strong and protective. Tony had never hugged Xander that way. Xander inhaled the smell of his father, cherry pipe tobacco and some kind of cologne.

"I am proud of you son and I am sure that you will make me even prouder in the future." Sirius whispered. "Don't let me or anyone put any expectations on you. Live your life how you want it not how others tell you to live."

Clearing his throat he backed up a bit but kept his hands on Xander's shoulders.

"I might not have got much time with you but I have learned about your and you will learn about me. I will give you the same advice I gave my godson. Those we love never truly leave us." Sirius said before poking him in the chest over his heart. "They stay right there. I'll hold you in my heart kiddo."

Sirius smiled at him before slowly disappearing. Xander passed out.

The End.

Spells Used in this Chapter:

Fornar Dubreai – A mapping charm a witch or wizard can used to determine their location if they know maps or coordinates well enough. Created by Isebas.

Teresten- The plucking charm. Normally used to pluck stubborn or unwanted hairs. Overpowered it can be used to pluck multiple hairs. Created by Isebas.

Lumos Solem- Issues a bright light from the user's wand that mimic's sunlight. Excellent for use against certain types of vampires.

A/N: I love BTVS/HP crossovers with Xander as a wizard. Hope you enjoy this one. I will always make a list of spells at the end of chapter in case anyone wants to use them. If I make them all I ask is that you give me credit and I will do the same with others.