Summary: Ougai Mori—Yokohama's most infamous underground doctor—is a formidable genius with a reputation on the same level as the Port Mafia's. His clientele and contacts range from the aforementioned Port Mafia to the Japanese government's Special Abilities Department. Ougai Mori's least known trait is his proclivity to somewhat accidentally adopt children with special abilities. Dad!Mori.

The Setting Sun

—Osamu Dazai

Warnings: an attempted suicide is described.

Mori watched the rise and fall of the sleeping Port Mafia Boss's chest. It was an odd thing, to see a man like that sleep.

One might expect a mafia boss and prolific murderer to experience constant nightmares, either out of psychological knowledge or a sense of justice. Mori had no such expectations. It was odd for him to see such a powerful man sleep because sleep was a reminder that even the most dangerous had weakness. Even the most clever could be caught unaware. Even the most powerful could be dethroned.

Mori stood up. He slipped his medical bag onto his arm and exited into the office.

The Boss's bedroom connected to the office. Considering the large amount of hours required, having a place to sleep nearby made sense. Plus, the Port Mafia Headquarters was a modern fortress. If the Boss was safe anywhere. . . it would be here.

The knocks on the large double doors of the Port Mafia Boss's office were muted, but Mori still heard them. They lacked the crisp sound of someone using their knuckles. They were made with the back of someone's hand. It was a polite type of knock, three short, quiet bursts.

Mori pushed one of the heavy, oak doors open. "My apologies, but the Boss is resting." It wasn't unusual for such visits to happen early in the morning, the Port Mafia never stopped working.

The person knocking was a young woman, her age somewhere in her late teens. She wore a pink kimono and her red hair was braided. "Who are you?"

"Ougai Mori, a doctor. And you?" He placed her as an ability user, and with consideration for her kimono and hair color, correctly predicted the young woman was the one with the ability Golden Demon.

"Kouyou," she courtly replied. She swept her eyes over the man and accepted the answer. The white coat, lazy smile, and slightly stubbled chin, fit well with the image of the doctor she had heard about.

Mori noticed the papers in her hand. He gave a close eyed smile. "I can put your report on the desk for you if you'd like, Kouyou-kun."

Kouyou eyes narrowed at the sudden familiarity. She brushed it aside-the offer was more important. "That would be appreciated."

XXX

Mori had a bag of groceries in hand.

The pathway-made of loose pebbles-crunched and shifted beneath his feet. It stayed a meter or so away from the river, so the path was dry unless it rained.

He spotted the bridge in the distance. Once he got there, he needed to take a right to get back to the house.

Spanning the river was a stone bridge. It was an old thing, partially covered in moss. Despite its covering and the cracks, the structure still somehow managed to look mighty and noble. It was a piece of the old times that had held on, scarred as it was.

As Mori drew closer, he noticed the child on the bridge. Not on it—as in on the regular walking part—but on the wide railing made of flat, rectangular stones.

The boy's brown hair was perfectly combed. His clothes fit him well and were on the expensive side. He merely stood there, on top of the wall, staring down at the water.

The thought crossed Mori's mind that the boy might accidentally fall in.

The boy did fall. But it was not by accident. The boy seemed to laugh as he stepped forward off the bridge.

Mori cursed. His grocery bag dropped onto the pebbles. He had to move, fast. The current was going in the other direction. He sprinted down the path. Pebbles flew out from underneath his feet.

He got in front of the child-the location evidenced by the brown hair bobbing up occasionally-and waded in. Mud sucked at his shoes, trying to pull them off. Water slipped into his socks.

The water was shallow enough that it came up to his chest and no further.

The boy drifted towards Mori; his eyes were shut; a dreamy smile was on his lips. He was still as a corpse, only moved by the current propelling him along.

Mori hoisted the child up from the armpits-the boy was complete deadweight, but fortunately only about eighty pounds soaking wet. A few steps got the doctor to the river bank.

Mori laid the child on the bank and checked for breathing-there was none. He only had to pump the boy's stomach for a few seconds.

The boy spat out two mouthfuls of water, groaning.

Mori rolled the boy onto his side. Still crouched on the muddy bank, he looked to see if there was perhaps a parent—or anyone really—nearby who would hopefully be the child's family.

Mori sighed. He was out of luck-there was no one else.

Well, whenever the kid woke up, he should be able to tell him where he lived.

Mori almost reconsidered at the thought of how hard it would be to explain to the parents that their boy tried to drown himself. But the boy needed to be watched for secondary drowning and if he stayed in those clothes he might get sick. Plus, saving the boy and leaving would be a bit suspicious.

Resigned, Mori summoned Elise.

Elise tried to pick up the boy.

The boy's eyes snapped open and he grabbed Elise's wrist.

Elise vanished.

The boy hadn't been expecting it either. He quickly snuffed out his expression of surprise and interest.

Mori recognized the sharp intelligence that hid in those cold, apathetic cinnamon eyes. "Do you have anywhere to go?"

"No," the boy said.

It was a lie. He had somewhere he could go. . . he just didn't want to.

Mori stood up, his shoes squelching as he did so. Elise reappeared, quickly leaving to go get the groceries Mori had abandoned. "Then you can come with me if you want."

The boy's stomach growled loudly.

Mori huffed a laugh. "I promise there will be food."

XXX

"Name?" Mori asked. He put the bag of groceries on a counter. He waited a minute, giving the boy a chance to respond. "Me first?" He smiled. "Ougai Mori, a doctor."

"Osamu Dazai."

"Alright, Dazai-kun. You can stay here as long as you want." Mori waved his hand and Elise disappeared.

"Can I leave anytime I want?"

"Of course. Go out the door anytime you like," Mori casually reassured. He hummed, checking his watch-he tapped the face a few times, water had gotten into it when he picked Dazai up. He checked the clock on the hallway wall outside the kitchen. "Yosano-chan should be back soon. I should get dinner started."

Dazai floundered for a few minutes, silent. He did not understand what was going on at all. "Don't you have any more questions?" Like. . . anything about why he was trying to drown himself? Or not having a place to go back to, even though he was pretty sure Mori knew he was lying and just hadn't called him out.

"Yes," Mori answered simply. He turned around, putting a hand on the kitchen counter behind him. "Do you want to answer them?"

Mori saw the despair in the way the boy held himself; the dead look as the boy replied, "No."

"Then I won't bother asking."

XXX

The Next Morning

Yosano waited until she got her new friend into a good mood before asking, "What's the name of your ability? Mine is Thou Shalt Not Die." Her smile didn't falter as she explained, "I can heal injuries."

"No Longer Human. I can cancel other abilities out." Dazai moved on before the meaning could settle in Yosano's mind. "Mori-san, what's yours?"

Mori looked up from the bottles of ointment he was sorting through. "Vita Sexualis. Elise is my ability."

Dazai nodded—his suspicion about yesterday was confirmed. Elise being an ability was the only real explanation for her disappearing and reappearing.

XXX

Four Days Later

"I see you've taken to wrapping yourself in bandages." Mori brushed his thumb over Dazai's wrist, where he knew several silver marks lay hidden under the cloth.

"Yes, Mori-san," Dazai carefully replied.

"Why do you hide them?" Mori inquired, his voice neutral. "Do you think they are ugly? Do you think they are shameful?"

Dazai hesitated. "I don't like the look you and Yosano-chan get when you see them." He admitted, part of the truth—the least concerning part of it-to satisfy Mori-san.

Mori kept eye contact for a few seconds. He nodded and let go of Dazai's wrist.

XXX

Mori was sitting on the couch, reading.

Dazai plopped himself on the couch. He stretched himself out, propping his chin on his hands. "How can you find happiness?"

Mori almost choked at the question, but managed to repress the urge. He was not expecting such a philosophical topic to come up. He let his gaze trail over a sentence, listless. "I can't exactly say for sure. There's not really a formula for obtaining happiness."

Dazia pouted. "Any ideas?"

Mori sighed and closed his book. "The materialists and hedonists are wrong, those who believe the material world is all that matters: the poor and the rich can be just as miserable. Financial status does not determine happiness. As for people out solely for pleasure: they find it and it slips out of their grasp so they endlessly chase it without regard for anything and everything else. People out to do good often create the largest amount of problems, as they have good intentions but horribly execute them, they are. . .the most happy, especially if they don't muck things up. Dazai-kun, there are many miserable existences and paths in the world."

Dazai's eyes were thoughtful.

Mori's gaze slid towards Dazai. "But, if you're searching for an answer to life and searching for happiness, then I'm afraid you won't really take any of my answers."

Dazai gave a wry smile.

XXX

Mori kept track of Dazai. The boy had left occasionally. Considering the calculating and careful attitude Dazai had when coming back, Mori suspected it was to test whether Mori had been lying about being able to leave whenever he wanted.

After the first two weeks, Dazai stopped acting suspicious. He never said it, but he had chosen to stay.

XXX

When Mori was away for work, he almost always left Elise at the house to watch Yosano and Dazai.

Mori considered leaving the two alone home dangerous because of two things a) they were children and b) they were ability users that a lot of people would pay millions to get their hands on. The first was good enough for Mori keep an eye on them-both together meant there was no way he wasn't having Elise there.

XXX

Mori hadn't seen Kouyou for a while.

He decided to eavesdrop while in the most popular break room in Headquarters. Sure enough, three guys were talking about it.

They said she was dragged back by her hair, screaming and kicking. They said apparently she had a lover and the two planned to defect. They said the Boss had been personally involved. They said the lover had been killed by Kouyou.

Mori finished his coffee and left the break room. He went into the elevator and selected the Basement level. He watched the numbers tick down and the doors open, then got out.

The Basement level looked normal.

It wasn't.

Mori fumbled around in a darkened corner for a moment. He found the small slit that marked the keyhole. He fished out his key.

He went down several flights of stairs.

'Level B9', the sign on the door said. This was a floor of holding cells. It was usually for attempted traitors.

Mori peeked inside several cells before finding Kouyou. He summoned Elise and slid the door open wide enough to walk in. He locked it behind him, but that was a frivolity. If either of them wanted, they could easily use their abilities to escape.

"What happened?" Mori asked, not unkindly.

Kouyou gritted her teeth and clenched her hands together. She spoke with a quiet rage simmering underneath the matter-of-fact tone she used.

Mori listened intently. The story was rather similar to the gossip.

Kouyou finished.

Mori stood up. "I can relate," he casually said. He smirked. "I don't want to be here either. I was blackmailed and extorted after all. Unfortunately, I should be going now."

Kouyou's eyes went wide. Her surprise distracted her from her anger.

Because that was treason. Blatant treason.

"Wait and build up your reputation again," Mori advised. "Regardless of what you do next, you will have to build that up. And reputations take time. Do not be impatient. Good luck, Kouyou-kun."

XXX

A Year Later

Yosano and Dazai stayed out of the rooms when the patients were there. It was one of Mori's rules.

They were happy to comply. Because even upstairs, they heard things.

Sometimes. . .there were medical complications. It wasn't always safe to knock people out or give them anesthesia.

Tonight, was one of those cases.

Another scream ripped through the house, burrowing into Yosano's and Dazai's ears as they tried to sleep. As the screaming had continued on and off for many minutes, the voice of the man became hoarse.

Dazai had already chosen to sleep with Yosano that night. This was common practice for them at this point.

The amount of patients Mori took on drastically increased last week. The Port Mafia was getting involved in more turf wars. . . unnecessarily.

The screaming finally stopped and the door to Yosano's room opened. Mori peeked in.

He listened to their breathing patterns. The children-he knew Dazai was there too-were sleeping soundly. Mori quietly closed the door.

XXX

Ranpo, Dazai, and Yosano had claimed the couch for themselves. Their eyes were glued to the television.

Mori, sitting in one of the armchairs, was keeping an eye on the murder mystery show. Partly to make sure it wasn't overly bloody and partly to scoff at any inaccuracies.

During the commercial break, Dazai and Ranpo chattered about their deductions. Yosano occasionally offered a thought, but preferred not to talk.

"But what about the sick person?" Ranpo asked.

The three children looked at Mori. He would have the best medical knowledge out of them after all.

Mori raised an eyebrow but answered. "Dazai is right. That's a common misconception about antibiotics. They work on bacteria, not viruses. Considering the symptoms, it is a virus that caused the illness."

Dazai smirked at Ranpo in triumph.

Mori coughed pointedly to draw the children's attention once again. "The question then is whether the writers of the show knew that—many don't. If they did, Dazai's theory is correct. If they did not, Ranpo's may be. Which one is it?" He shrugged. "Sometimes, people are smarter than you give them credit for and sometimes they are much more stupid. When deducing, try to account for both and see where it goes."

XXX

Kouyou was taking a risk. "Will you help me, Mori-sensei?"

"Perhaps." Mori was capable of authenticating the Boss's murder as death from his illness. "I have some conditions."

Kouyou's face grew more guarded at the answer.

"I can do the fake autopsy, but I will not be your witness. I get to leave the Port Mafia. The neutral territory I possessed will be returned to me. I want you to reform the Port Mafia as you have said you wanted to."

Kouyou frowned. "How will I explain your absence?"

Mori waved his hand. "I never really joined the Port Mafia. I'm still an outsider when it comes to general opinion. If I'm not the witness for the Boss's death, there's no need for me to stick around long. I can forge a call from the Boss to give you two a reason to be there. I can also forge a contract and put it in my file. A clause for a certain period of time will work well for our causes."

XXX

Mori opened the door. "Hello, Fukuzawa-dono. Are you in a hurry or would you like some tea?"

"No hurry, Mori-sensei," Fukuzawa assured. He toed off his shoes and placed them neatly at the entrance. "How did it go?" He followed Mori into the kitchen.

"They had fun," Mori assured. His statement was confirmed by the laughter coming from the living room. "Any preference of tea?"

Fukuzawa shook his head and sat down at the island.

Mori poured two cups of hot water. He put in the tea leaves and slid one cup over to Fukuzawa. He hummed thoughtfully. "How would you feel about Yosano-chan and Dazai-kun sleeping over next week?"

Fukuzawa narrowed his eyes, Mori had never suggested something like this before. "Is there a particular reason you want them away for a night?" His tone was slightly chiding.

Mori smiled cheerfully. "I'll be out of the house and I don't want them to be alone."

Fukuzawa knew Mori usually left Elise at the house. If it was something Mori needed Elise for, it was dangerous. It probably had something to do with the Port Mafia, but it wasn't Fukuzawa's place to pry. He was being entrusted with his friend's children, with the knowledge that he would keep Yosano and Dazai safe in case something happened. He nodded and picked his cup of tea back up. "That sounds doable. Could you drop them off or do I need to pick them up?"

XXX

Mori had been ignoring the suspicious looks from Dazai ever since the boy heard about the sleepover.

Eventually, Dazai just came out and asked, "What do you want us out of the way for?"

Mori snorted at the way it was phrased. "I am going to do something very dangerous," he admitted.

"And if you don't do it right?" A hint of emotion entered Dazai's voice.

"I'll probably die," Mori candidly replied.

Dazai furrowed his eyebrows in no small amount of confusion. "I thought you didn't want to die?"

"Sometimes, Dazai-kun, there are things we have to do that that we don't want to."

XXX

The rain drummed on the roof. Thunder could be heard faintly, amidst the steady patter of droplets.

Dazai was on Mori's lap. He was less thin than two years ago but still a twig. His arms were draped around Mori's neck. Yosano's head was leaned against Mori's chest, his arm wrapped loosely around her. Mori resigned himself to going to sleep on the couch and surely waking up with a crick in his neck tomorrow morning.

A/N

Dazai has appeared. He really needs therapy, but that's hard to get when you're a runaway.

Philosophical conversations will also be a thing. Why? Because I love philosophy. And this is Mori and Dazai, there's no way they don't have conversations about philosophy.

Please don't ship any of the kids (or, the adults) here. This is all pure sibling and fatherly—pure familial—relationships, nothing romantic.

Timeline note: Mori is 28, Yosano is 13, and Dazai is 9 by the end of this chapter.

Chapters:

1-Mori

2-Yosano

3-Fukuzawa

4-Dazai

Next: 5-?

-Silver