Sirius Orion Black wasted no time after his godson left in the morning.
He immediately called Dobby and put him on the case! He may be mad as a hatter, but he learned enough about how these kinds of things worked as a Malfoy elf. Winky's experience with the Crouch family wouldn't hurt either. They'd find a good house. Devil shapeshifting magic wasn't owned by humanoids, even if they could only grow to very short human-sized.
Did his godson think he had any experience purchasing property? He spent his adult life having his soul sucked out or floating in some kind of death dimension.
Lord Black noticed that Dobby's clothes matched before he popped away. Maybe Winky dropped the hammer on his wardrobe? They still were a bit odd, like a musketeer outfit or something? At least it wasn't mismatched.
Important business taken care of, the Knight decided to take the Padfoot out for a walk. Chuckling to himself at his bad jokes, he cast a Notice-me-not, transformed, and dashed out of the city, towards the countryside.
Before their trip to Japan, he and the pup sparred for half a day, figuring out their new powers.
In a raw contest of power, Harry only needed to hit him with a blast of magic to stop him. The boy would have had him out for days if not for Fawkes on standby. One blow crippled him!
That is if he could hit him in the first place.
Harry was right when told him that their old wizarding magic would be mostly useless in combat. At first, Sirius was genuinely he would be a waste of a chess piece as a devil, letting down his godson again.
He had learned a bit of fencing as a child and was fast, but that didn't translate to much.
Then, Harry suggested that he turn into his Grim form.
Padfoot was a dance of death. He was able to push his paws against the air to change directions. His body was able to partially dematerialize into a foggy phenomenon. Both changes were flashy, but it was his senses and speed that made him an actual threat.
Grims were known as bad omens, heralds of death. And Sirius planned to be one as well to help Harry out when he could. He'd died once and felt like death more times than he could help.
That was until Harry experimented with barrier magic. The boy had so much power that Sirius found it literally possible to break through. Stupid devil ranks and low powers. Dobby even beat him in a fight! The little bugger claimed it was because he didn't know his magic as the former elf did, but it didn't help Sirius' pride much.
At least he knew he could strengthen his body through vigorous exercise. So, when he got outside the city limits, he bit a tree until it timbered to the ground and used it as a weight to strengthen his neck and jaw.
He would have tried a boulder first, but he didn't want to risk his teeth. Maybe next time.
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Padfoot trained until he was sore, but didn't exhaust himself in case of a fight that could pop up. His quick course of Auror training during a civil war taught him that much.
Still thinking of helping his godson, Sirius decided to practice with his enhanced senses. His nose would have made Moody jealous.
'Moody... at least you found someone out there,' he thought to himself, wiping a small tear from his eye. Sirius had been pushing his vacation in the Veil aside so far. He didn't want to think of what happened and what was left behind.
"I know!" he muttered out loud, ignoring the weird look from a passing stranger. "For Moody, I'll practice my senses and get laid. He would have appreciated that!"
So Sirius sniffed.
He got walked through Kyoto sniffing. He caught a train while sniffing. He got some quality British cuisine at a hole in the wall shop wall sniffing. Finally, when he was about to give up and head to the hotel suite, he sniffed and caught something new.
Magic always had a buzzy smell to it. The wards on a house or the ones that covered the entire city all had a smell that was like inhaling clean pollution. If there was a difference in smell depending on different casters or races, Sirius couldn't tell the difference. He was new to this though, mundane smells were more difficult to pick out, but the magic in the air didn't make his everyday life any worse or better. It just was.
The supernatural races, however, stood out like stars in the night sky.
Devils smelt like fire and passion without smoke. It hit him in the face with their brunt nature that demanded attention. Reincarnated devils, however, were a little more muted.
No, muted was the wrong word. They were subtle, more controlled.
Harry was a weird case in how he smelled like a pureblood devil, but the unique way he was turned is obviously to blame. Or maybe he just smelled the special powers like he had over death or how the Sitri broad was supposed to have power over ice?
This new smell was different. Lust.
It hit him hard like walking into a hotel room that had been locked up for a weekend, full of nothing but wonderful debauchery. Angry, beautiful, drunk depravity that only existed in his raunchiest of dreams that had been trapped until the perfect time where it was scattered to the winds. Yet, at the same time, it was tempered by power and a touch of unashamed self-hatred.
How his nose could smell concepts and contradictions, Padfoot didn't care. He headed straight towards the smell, into a bar and met a dangerous woman with dark hair and dangerous violet eyes.
The two features were shared with his cousin, the bad one, but that was the furthest thought from his mind as he tried to seduce her.
She complained about her job and stupid assignment where she had to sit in this shithole town watching a useless child for equally useless reasons.
She complained about the boss of her boss that would never love her, no matter what she did.
He played the role of a douche. They both knew she was just using him to get over frustrations, but Padfoot didn't have it in him to care.
He wasn't an idiotic child though. He wasn't obsessed like a teenage James Potter. Sure, he wanted nothing more on this night than to have her, but he used a bit of his smarter head to think. He'd never bring this bird to the room where he and Harry were staying. He offered to get a room, but she took him to her place.
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She started rough enough to break bones on a regular human.
The look of surprise on her face when he pushed back, proving he was NOT a regular human was enough for Sirius to know that this woman was even more dangerous than he thought. He was fully aware that she would have screwed him to death if he was as he was a few years ago.
Sirius was sure she must be some sort of succubus until the feathers flew through the air and black wings appeared.
They were on the walls, the ceiling, in the air. They broke a bed, a couch, and a marble countertop.
When they finally finished, both covered in the gleam of sweat, she said, "That was the best sex of my entire life."
"That..." Sirius almost gave an empty platitude. Something he would have said after a tumble in the broom closet. But he couldn't, she stated his thoughts exactly. So instead of talking, he whipped his wand out of his holster and cast a Reparo on the house, making everything like new. While he was at it, he reformed his clothes out of the tattered, bloody scraps scattered across the room before he felt a cheeky grin on my face.
"So I almost feel bad that I have to kill you."
That beautiful voice he loved to hear scream his name got Padfoot Jr. excited, but he had to live. Harry's mind might break until he found a way to bring him back again to torture him if he died again.
So he wasted no time turning into Padfoot and pushed his paws upwards while he lied on his back like when he jumped on the air.
The Fallen flew up and hit the ceiling, dropping her spear of light in surprise.
It gave him a nasty cut, but he'd live. He barked a goodbye, made his lower body incorporeal for a moment, flew to his paws, and barreled through a window, shattering it with ease.
She chased him as he frolicked like the star crossed lovers they were. Raynare. It only took the paranoid, murderous bitch three orgasms to tell him her damn name, but it was all worth it.
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It wasn't worth it. This morning he'd been slapped and walked out on for the second time since his time with Raynare. Regular, a human woman just didn't do it. He was Superman.
And a real-life Superman can't hold a glass doll.
The pup laughed like the Dark Lord he was while milk squirted from his nose.
"Looks like God's gift to-OW!"
The damn pup kept laughing at him while he held his sides.
"Can't grace mortals anymore," he pouted as he grabbed breakfast that was expertly prepared by Winky.
"Finally!"
Sirius looked to his exuberant godson in confusion. He was busy casting cleaning charms and ruffling his hair.
"A contract came in. One for retrieval of stolen goods. I didn't really want to throw myself into danger, but its just wizards, I have the cloak, and it's hard to lie about these sort of things to the spell."
His King cracked his neck once, sprouted his wings, winked to him, and disappeared in a show of lights.
"Hmm..." Sirius bit at his inner cheek as he sat at the empty dinner table. "Maybe I should look for that crow again?"
It may have been a stretch for Kokabiel's Fallen to have been sitting in Kuoh for six months watching Issei, but the Three Factions should be slow moving and patient when there isn't a battle to fight.
Also, there were two sisters of Maous living there. Honestly, it's reasonable that there should be a greater Fallen presence there than there was in canon.