A/N: Sorry about the long wait. Between graduating, preparing for departures, and getting depressed over Puella Magi Madoka Magica, finding time to write this chapter became terribly hard.

"Aren't you going to go in?"

Harry Potter turned to the voice. 'Staring' back at him was a featureless face. The being tilted its head at him in curiosity. It was a curious little thing, about his size but with no body. In the vast whiteness of his current location, it should be invisible but the dark 'glowing' outline around its form gave it enough contrast to be discernible from the white canvas.

Behind it was an ornate double door, decorated in various depictions of magical animals. Dragons, manticores, unicorns, and many others were carved into its bone-white surface. Harry frowned, thinking of a way to escape his situation. He was powerless at the moment. His magic was unreachable and his body was bruised and battered, a sign of having survived an intense battle.

Harry looked back at the figure and replied in a firm tone. "No. Send me back."

Although the figure didn't have any features to speak of, it still gave Harry the sense that it was raising its eyebrows at him.

"No?"

"No," Harry repeated, "I was chasing a man and followed him here. If that door leads to where I think it does, then I'd be an idiot to follow."

He could've sworn it was smirking at him.

"You don't seem surprised to see me." The being noted.

"Are you God?"

The figure's grin broadened.

"Who knows? Am I God? The universe? The truth?"

It pointed a finger at him.

"Or am I you?"

Harry snorted.

"If you were me, then you'd know that I do not seek what is behind the Gate."

"Of course, of course. You don't want it now."

Harry frowned. He got the feeling it was implying something.

"There is nothing for me here. Please send me back."

"Very well, I'll be sending you back, though I'd be taking this as payment."

Harry's eyes bulged as he felt around in his pocket for one of his most prized possessions. It was gone.

"So this is what happens when a mere concept gains … awareness," It mused to itself, twirling the Elder Wand in its fingers, before snapping it in half, the separated pieces dissolving into dark smoke, "They become insolent little things. Wouldn't you agree?"

Harry had no idea what the creature was talking about. His mind was still reeling from the loss of the Elder Wand.

"Death had been overstepping boundaries lately. Unfortunately, it does not fall on me to reprimand my brethren." It continued in a remorseful tone.

Its grin broadened even more as it turned its full attention on Harry, almost splitting its face in half.

"Ah, but you really must be going. I look forward to our future transactions."

Before Harry could demand an explanation, he found himself back where he had chased the Dark Lord to. Unfortunately for him, this one was smarter than Voldemort. More powerful too. Looking around him, he briefly wondered if his encounter with the being in the white place was real. His only proof was the missing Elder Wand. Oh well, he'd done just fine without it before, and knowing that his quarry went inside the Gate made Harry certain that he was most definitely dead.

There was no surviving contact with The Eye.

In fact, it was a miracle that Harry was able to escape with his life.

With a relieved sigh, he started his journey home, to inform the masses of the Dark Lord's demise.

It had been a long and hard-fought war, making the one against Voldemort pale in comparison. It was not only Britain that was almost destroyed by the madman, but most of Western Europe as well.

It was an anticlimactic ending. Harry had been expecting a grand battle after going through the man's numerous minions, only to find out that the idiot had killed himself.

It was finally over.

The Dark Lord was dead.

Or at least Harry thought until the sky fell.

2.

Harry woke with a gasp. He had not dreamed of the past in a long time. An ominous feeling settled in his gut, making him embrace his wife tighter. She moaned in her sleep, mouthing 'more'. With a smile, Harry stroked her hair lovingly before getting out of bed.

And stumbled upon a petrified cat.

Their cat Kuro was standing still on its feet, eyes wide open and unmoving.

Curious, Harry poked the cat on its side.

It toppled over.

He could tell the cat was still alive. With a burst of magic, Harry woke the cat.

The moment Kuroka's eyes landed on him, her eyes rolled to the back of her head and she fainted right away.

With a frown, Harry scratched his head, his tentacle making a squelching sound.

Wait, tentacle?

With a facepalm, Harry returned back into human form.

It was no wonder the cat was terrified.

Oops.

3.

After sending a letter to the devils that he denies them entry into his territory, Harry started to prepare breakfast.

Preparing breakfast was something that Harry was used to doing. He had cooked for his relatives for most of his childhood after all. Unlike from before however, Harry cooked with a smile on his face. His food was filled with his love and affection, which Yasaka claimed made his cooking taste like paradise.

Harry didn't know if that was true but he wasn't going to turn down the reward sex afterward.

With a smile on his face, Harry carried the food on a tray and went back to the bedroom.

With a gentle nudge, Harry woke Yasaka and presented her with breakfast in bed.

Yasaka smiled at Harry in thanks. She was lucky to have a thoughtful husband. Harry knew that after last night's… activities, that she would be in no position to stand and make breakfast the next day.

Sure enough, Yasaka still couldn't feel her legs. With a grateful nod, she began to eat, glad that Harry cleaned up all the bodily fluids that covered the bed, the walls and the ceiling from their love-making.

Such things could make one lose their appetite after all.

The door opened and Kunou walked in, rubbing her eyes. She immediately spotted Kuroka unconscious on the floor and rushed to cradle the cat in her arms.

"Wah! Papa, Kuro-chan's dead!" She rushed at him in panic.

Harry chuckled and patted Kunou's head, assuring her that the cat was not dead.

With a wave of his hands, Kuroka's eyes snapped open. In a wave of panic, she shot out of his grasp and landed in Kunou's arms, frantically trying to get away from what she thought was a tentacle monster in human form. After witnessing what such a creature was capable of last night, it was no wonder that she was terrified.

Oddly enough, her mind began to wonder what it would feel like to be in its slimy hold.

"Shh, there, there, Kuro-chan." Kunou scratched Kuroka behind the ears, while rubbing her softly, something she found last night could for the cat into compliance if it ever was in one of its moods.

Sure enough, Kuroka turned into a purring puddle of fur under her ministrations.

Smiling proudly, Kunou clambered up beside her mother and began eating as well. Yasaka absently wiped the dried drool on her daughter's chin as she looked up at her husband.

"So what are your plans for today?"

"Grading exams." Harry replied with an exaggerated wince.

"There, there." Yasaka patted Harry in mock sympathy. "Putting in all those zeroes must have been hard work."

Harry was about to reply but stopped when a tremor shook the barrier around Kyoto. Judging by the disturbance, whoever ran into it must have been quite powerful.

"Devils." Harry sighed and stood. Yasaka's expression immediately darkened. She made to get up but Harry gently pushed her back down.

"I'll take care of it."

Yasaka wanted to protest but Harry kissed her on the lips, cutting whatever she was about to say, before turning on his heel and disappearing.

4.

By the time Harry got to the barrier, guards were already swarming the place, pointing weapons at the devil outside. The red-haired devil did not seem intimidated in the slightest, smiling pleasantly at the assembled youkai. At Harry's approach, the youkai parted to allow him through but did not lower their weapons.

"Ah, you must be Harry Potter." Sirzechs began. "I came regarding the letter you sent earlier. I was wondering if we could—"

"You got some nerve, showing your face here, of all places."

Sirzechs was not undaunted by the cold response. He kept the pleasant smile on his face as he continued to talk.

"I did not come here as the leader of devils, but rather as a brother wishing to secure his sister's happiness. I had hoped to keep old grudges out of the discussion."

The youkai around Harry bristled in fury. The nekomata genocide had occurred not even two decades ago. For Sirzechs to dismiss it as ancient history was maddening.

Harry discreetly sent calming charms on the youkai. It would not do if one of them get hot-headed and decide to attack the maou. The guards were still young and inexperienced in hard combat. Attacking a maou is universally known to be an act of suicide.

"Your letter that arrived this morning stated that you would be unwilling to host a few devils in you territory of Kuoh. I came to make an offer in exchange for allowing my sister and her peerage—."

"No."

"Ah, but you have not even heard what I am willing to offer yet." Sirzechs pouted, an expression that looked disturbing on an adult male.

"Look, you and your kind are not welcome here or anywhere else the youkai had taken as their home. That is not going to change anytime soon. The fact that you came without hostile intent and remained outside the barrier is the only thing stopping us from obliterating you on sight."

Sirzechs looked amused.

"Oho? That is quite the bold claim to make." Sirzechs chuckled. "I may look like this, but I am one of the maou, you know."

"This barrier may be top of the class, but it wouldn't stop anyone above high class from forcing entry." Sirzechs continued, his hand reaching to touch the glowing barrier.

The sound of an object breaking the sound barrier echoed loudly as Sirzechs found himself being thrown back, his cheek stinging. He spread his wings to stop his momentum and looked around himself in surprise. He had been blown back quite the distance into the forests surrounding the youkai territory.

The one who had punched him in the face stood on a tree, looking down at him without a hint of fear. The mask hid its identity but the black wings identified it as a karasu-tengu. It was garbed in dark colors, so as to blend in its surroundings better, very reminiscent of ninja clothing. All around Sirzechs, many other hidden youkai dressed in a similar fashion emerged.

In no time at all, Sirzechs was surrounded by the youkai ninjas numbering in the dozens. Normally, Sirzechs would not be bothered by this at all. However, these were not normal youkai. He sensed that they were using an energy he hadn't felt since the nekomata incident.

The youkai ninja were filled with natural energy of the world. They were using senjutsu.

A bead of sweat rolled down Sirzech's brow. Senjutsu is a technique that is able to put someone on the level of ultimate class with enough training and judging by the looks of these youkai, they were veterans at the art.

A loud pop pulled Sirzech's attention to Harry, who had appeared from thin air. The green-eyed man looked sternly down at the maou.

"If my wife was here, that act alone would have resulted in her declaring an all-out war against your faction. What was the point of doing that anyway?"

Sirzechs scratched the back of his head sheepishly.

"Ah. You should know that many devils had their eyes on the youkai faction for a while now. As it is, only fear of the unknown has stopped them from outright attacking and taking the youkai as theirs. I merely wanted to demonstrate how futile barriers will be against a determined devil that wanted entry. If you'll allow my sister to study in Kuoh, then I'll personally make sure that no devil will bother the youkai ever again."

Harry deleted the rising fury within him. Getting angry now would be counterproductive.

"You're a bastard, you know that?"

Sirzechs smiled more brightly. "I am a devil afterall. And as a brother, I'd do anything in my power to ensure my little sister's happiness."

"This is a waste of time." Harry declared. "I don't care about what you have to say. Devils will never come within a hundred meters of the youkai while I still breathe."

Steel flashed within green eyes as Harry stared the maou unflinchingly in the eyes.

"So I kindly ask you to leave before I make you."

"You may be a Magic God but do you think you can do that so easily? I have no plans on leaving until I secure a place for my sister, even if I have to beat a Magic God to do so. But you should know, a fight between us will be catastrophic. Are you willing to risk so many lives?"

Contrary to Sirzech's expectation, Harry grinned at him.

"You seem to be misunderstanding something here."

Sirzechs raised an eyebrow at the (happy?) attitude.

"There will be no fight at all." Harry declared with a shake of his head, confusing the maou even more.

While Sirzechs was confused, Harry began to hack the universe.

Logging in.

Entry found.

Sirzechs Gremory (Lucifer)

Species: Devil

Rank: S+

Maximum magical output: 375 x 2^50

Changes saved. Maximum magical output changed to 10.

With that done, Harry commanded the elite ninjas of the sage corps.

"Toss him out."

As the senjutsu-wielding youkai ninjas advanced upon him, Sirzechs realized that his magic power had fallen to almost nonexistent levels.

In the face of such overwhelming odds, the maou gulped. Maybe coming here was not such a good idea after all.

End

A/N:

This chapter was terribly hard to write. I feel as if it didn't flow like the first two. I don't know how to progress without doing so. If anyone has suggestions, please tell me.

Someone pmed me about power rankings. Honestly, I haven't really given it much thought. The following is something I made on the fly.

Tentative Non-linear scaling. There are many things that I probably haven't thought about yet so this is subject to change.

This E~S ranking system applies only to MAXIMUM magical output. Cheat abilities like longinus class sacred gears are not quantified.

(x) refers to powers and talent obtained from birth (lineage).

Average Humans = 1(x). Untrained human.

Rank E = 1(x) x 2. Newly reincarnated devils without training or sacred gear

Rank D = 1(x) x 2^3. Two-winged to four-winged angel. Low-class devils with some experience and training.

Rank C = 1(x) x 2^6. 6-winged angel. Mid-class devils.

Rank B = 1(x) x 2^9. 8-winged angel. New high-class devils.

Rank A = 1(x) x 2^12. 10-winged angel. High-class devils

Rank S = 1(x) x 2^30. 12-winged angel. Ultimate-class devils. Lesser gods.

Rank S+ = 1(x) x 2^50. Super devils. Major Gods. Some Dragons.

EX rank reserved for beings and abilities that cannot be quantified within E~S ranking and falls under a category of their own. In some cases, the power ranking does not apply to them. For example, Shiki's Mystic Eyes of Death Perception can pretty much kill anything. He/She can kill Sirzechs in at least 1 hit if the Maou would just stand there and take it.

Tiers are classifications, not rankings. For example, if Touma were to punch Ophis, who in this story is a Tier 3 entity whose parameter values are infinite, with Imagine Breaker, a Tier 2 ability, Ophis will be destroyed in 1 hit.

Rank EX Tier 1 = Abilities of nigh absolute effect

Rank EX Tier 2 = Abilities of absolute effect.

Rank EX Tier 3 = Concepts given form.

Rank EX Tier 4 = Transcends universal logic.

Rank EX Tier 5 = Creates and manipulates universal logic

There are many powers out there deserving their own tier but I'm not listing them here. These are the ones most relevant in this crossover so far.

Rankings may be subject to change.

This power ranking system may be horribly wrong but this was only how I first imagined it so please forgive me if they seem wonky.

Thank you for reading.