Disclaimer: Sora no Otoshimono and Casshern Sins are respectively owned by Suu Minazuki and Yasuko Kobayashi in collaboration with Madhouse, not by me. This is being done purely for fun, constructive criticism is welcome and flames will be ignored.

A special recognition and thanks goes to The Infamous Man and Lucas Bane, betareaders and co-founders of this fanfic.


Heaven of Sinners

Chapter 1 - Failed Past

Unspecific Location

The room was dark. Almost all the lights were off, the only three alight dimmed and arranged to brighten the walls on one side, leaving the middle and the backspace coated in shadows. The only thing one could discern was the silhouette of a seated person, more a form painted by the difference in hue of the darkness than by any real color, the head supported by a hand under the chin and its eyes closed as if it was sleeping. At the other hand there was no doubt what was illuminated at the other end of the room.

Clocks. Tens or maybe a hundred clocks fixed to the walls, all different and all coming from many time periods: analogs, digitals, hourglass, sundials, pendulums, projection types, skeleton types, binary types, French rococo bracket clocks, Peter Henlein's "Nuremberg Egg", Su Song's Astronomical Clock Tower, Roskopf's pocket watch and many others, a few made of very advanced technology. And they were all displaying different times with no apparent rhyme or reason. The most striking feature, however, was that no clock, even the pendulum, made a single sound: the entire chamber was enshrouded in absolute silence, and only by straining the hearing to its very limit could one make out the shallow breathing of the hidden figure.

This silence was shattered when a lone clock, hidden among the others, emitted a tinkling 'Tling!' and began playing a blithe music, a composition many enthusiasts would recognize as one of the many masterpieces of a certain German pianist active in the Nineteenth Century, a genius who would often draw inspiration from childhood's tales about an island in the sky told by a kindly old man.

The Symphony No. 5 in C minor of Ludwig van Beethoven.

The eyes of the figure in the shadow shot open at the melody, sapphire blue in color and cold and unforgiving like ice, showing a great amount of surprise before the lips pulled back revealing the same cruel and eager smile a predator would wear after locating its prey.

"So you have finally awakened, Casshern..."


The being now called Casshern stared at the smiling Reikoku. He opened his mouth as to speak before closing it almost immediately, his features marred by confusion. After a second again he disclosed his lips and said: "C-Casshern?" His voice, while pleasant to the ears, was hesitant. "Is it my name?"

The Sky Master frowned: it was a truly strange question, one that didn't make sense. 'Why should he asking confirmation? It's almost as if...better be sure.' "That's right, you are Casshern. Don't you remember?" He said wearing a mask of gentleness.

Casshern weakly raised a hand, observing the appendage as if he was watching it for the first time in his life. His eyebrows narrowed like he was in the middle of some kind of exertion. "No. I...don't remember. I don't remember anything: my name, my past...all of them are shrouded in fog." With the raised hand he gently touched his face before turning once more to the Master, his tone full of hope. "But...you know, right? Who I am? Maybe also why I can't remember?"

Reikoku kept up an impassable facade, but inside his head was exulting. 'He doesn't remember! Anything! He completely lost his memories. This is...perfect! I can say whatever I want and he will believe it like the word of God. I just need to be smooth and believable.'

"Of course I know. But this is troublesome: is it an error with the programming?" Taking the brunette hand he helped him getting on his feet. Casshern faltered a bit but quickly found equilibrium. "Why don't you try running a System Scan?" 'A risky move, but it's not like I can avoid mentioning it. Let's just hope it is not reparable.'

"A System Scan?" At those words Casshern's left pupils grew bigger before strings of numbers and indecipherable glyphs started streaming inside his retina. When he spoke again his tone had changed, from insecure to bold and firm. "Initiating all Systems Scan. Preparing for a complete Hardware Analysis. Battle capacity...confirmed 100% functionality. Emotional control capacity...confirmed 100% functionality. Processing capacity...confirmed 100% functionality. Memory state...corrupted?!" He shouted, shocked. He brought a hand over the left side of his face, disbelief evident on his face. "Recovery data...failure. Personal History Restoration impossible to perform." His hand dropped and he looked at the Master. "How did I do that? I am...not a living being, right?"

"What? You don't know you're an Angeloid?" Before the younger Harpies could understand what she did Reikoku turned and shot her his most vile look, one which a promise of future pain. She gulped and didn't say anything anymore.

"Angeloid?" Casshern repeated. "Is it what I am?"

"Correct." Reikoku again faced Casshern putting up his best smile. "Your memory loss is most unfortunate, but I can easily fix it. My name is Reikoku, the 'Sky Master' and Lord of this land. I am an Angel, the name of the race who inhabits Synapse, the name of the place where you currently are. And you are an Angeloid, a droid built and modeled after the Angels."

A pause.

"Your name is Casshern, Generation Zero First Prototype-Class Angeloid." He raised both arms, flashing a slightly haughty smile. "And I am your Master: the one you were created to serve in any way I seem fit."

"...I see." Commented Casshern, for the first time a look of understanding on his face. "Yes… Synapse...and Angels."

"You remember something?" The Master asked, masking his worry.

"It appears the sub-routines were spared. When I heard those terms the data related to them came back to me." Suddenly he got down on one knee, put the left hand over his heart and bowed his head. "The title of Sky Master is granted to the highest authority of Synapse, Head of the High Council. I ask forgiveness for not having shown before appropriate deference for your rank, Master."

Unseen by all a strange expression passed on Reikoku's face before he resumed his fake amiable smile. "Think nothing of it. It isn't your fault for not remembering. The technicians assured me it was all right. Now, let's continue, Casshern." The six-winged man raised his head. "You were created to be a loyal protector of Synapse and Earth with your might. Some might call you a weapon but you're much, much more: you're a shield destined to protect the peace enjoyed by the Angel's entire race. There is a reason why I decided to activate you now."

A pause.

"But it can wait for now. I'm correct in assuming that, beside basic data, you don't have recollections of Synapse and how it looks?"

"Yes, Master." A dejected look passed on Casshern's face. "They're only simple descriptions, no images or video."

"Then why don't you go for a tour?" A midst everyone's surprise he pointed to the Harpies. "Those are the Harpy sisters, my personal guards. They will be your escorts and will show you how your home looks."

"My home..." Muttered the brunette. "I thank you for your generosity."

"It's nothing. You deserve it." Reikoku then turned and placed both hands on the sisters' shoulders before lowering his head and whispering: "Give him a complete tour of Synapse. Be friendly. DON'T"-here his voice changed to a hiss-"mention anything about Gehenna. He was already here in the temple when I called you. You haven't been briefed. You know nothing. And if he asked about the Downers, call them humans and don't you dare express distaste. Lie, lie for all you're worth but make sure to hammer the fact we're all magnanimous beings and we care for the Downers. Simply do it. And if the matter of the Angeloid traitors comes up, just say it's classified. Do I make myself clear?" They both nodded with wide eyes. "Great!" he exclaimed jovially, patting their shoulders. "Like I said, make sure he enjoys the tour. Now go. Go!"

With a bit of forcefulness he pushed Casshern and the Harpies away. He watched them exit the temple and disappear in the distance toward the island's border.

He stood here in the silence for a bit before turning back and sit again on his throne.

I ask forgiveness for not having shown before appropriate deference for your rank, Master.

"Idiot. That-" he muttered, his tone a strange mix of longing and bitterness. "-is something that I should be saying."

In the virtual center of his power the Sky Master sat, alone, recalling times long past.


The silence between them was awkward. The blonde, elder Harpy was no stranger to escorting powerful figures (even if only with the Master she deigned to take her job seriously) but this time the circumstances were...odd, to say the least.

Being careful to not being noticed she stole a quick glance behind her at their new 'cohort' following them, who was busy contemplating in silent curiosity the structures and the edifices surrounding the Sky Master's temple. Mostly consisted of halls and archives for the bureaucratic procedures of Synapse, procedures that nowadays were reduced to 'the Master commands, she and her sister obey', and laboratories to house Angeloid researches. The latter installed only recently following the deserter's crisis.

He was the fabled "Angel of Death" imprisoned inside the level sixty-six "Gehenna", the only prison of Synapse? A danger as great as it was vague? Taking into consideration crime was a concept unknown to the Angels as a result of their near-utopias society the existence of such a place had always been uncanny, even as a subject only spoke behind closed doors.

And she was supposed to accept that this good-looking boy was their equivalent of the earthen Boogeyman? If it wasn't for her Master's words and the fact they really found him inside the Gehenna...

'And besides-' She pondered, her eyes resting on the three pairs of wings. '-is he really an Archangel? Even if he is an Angeloid?'

Angeloids can't have more than two wings: this is a rule which can't be broken no matter what. That and the collars with chains served to mark the droids from the real Angels. Casshern had neither, nothing to distinguish him apart for the brief moment before when his eye displayed his artificial nature and the strange devices connected to his sides. They reminded her of guns but the shape and position were all wrong. If she didn't know better she would swear they suspiciously resembled a pair of...

"Is something wrong?" She was abruptly shaken off her thoughts by the question. Casshern was looking at her with a slight frown. Embarrassingly she realized that, so lost in her musings, she ended up staring at him. "Is there something on my face?"

"A-Ah no! Nothing wrong! I just wanted to be sure you don't end up lost." She waved her hand to emphasized how flimsy the subject was, uncaring of the puzzled look on her sister's face.

Instantly his expression cleared. "Ah. Thank you for your concern." He gave a small smile, and the two Harpies couldn't suppress a slight blush. The awkward moment was interrupted when the younger sister pointed with a finger to the sky.

"Nee-san. Look. Aren't we near enough to take flight?" And indeed from the aloft clouds emerged the silhouettes of numerous floating islands casting their shadows on the three. Even more higher in the sky the Sun shined with a warm glow. What they didn't know (and in the case of the two Harpies never bother to investigate) was that the temperature is always warm in Synapse and it never rain or snow. The same field that shielded the floating world from the eyes of humans also kept the inside immersed in an eternal spring despite the change of atmospheric conditions outside and the bitter cold of the great height Synapse is floating.

"You're right." She agreed. "Cass...Lord Casshern,-" She hastily added recalling her Master's warnings. "-will you require help with the flight?"

Casshern blinked before chuckling softly. "Lord? Please, I am not such thing. Please simply call me Casshern. And for flying...-" He slightly bent his knees and stretched his arms. As if following an unseen command his wings opened to their maximum length and a helmet formed around his head that covered all but his face, with a golden V-shaped headpiece on his forehead. "-I think my body remembers!"

With a loud 'CRACK!' of displaced air, he disappeared, leaving an imprint of a feet on the ground. Gasping, the two sisters looked up, mouths dropping when they found Casshern's figure again, hovering many dozens of meters from his former position.

'W-What acceleration!' They thought in unison. 'It's close to Delta's!' "Wait for us!" They shouted taking flight themselves.


Once regrouped, the Harpies led Casshern toward the more nature-themed upper islands. Even if his face stayed calm, Casshern's eyes were constantly sparkling with an almost childlike curiosity: ancient temples, parks and waterfalls with the water flowing from one island to the lower one, everything was a novel experience which filled his reactor with a strong, indescribable feeling. Unknown to him, that feeling was 'relief'. For what, he couldn't say even if he knew how to call it..

"This is Synapse...so beautiful." He muttered. They were at the edge of a huge garden covering an entire island, filled with flowers of every color and a humongous tree covered with lush green leaves in the middle. He knelt down before a patch filled with azure-colored flowers and gently touched one with his right hand. "It's so full of life."

"The upper islands were projected following a naturalistic and minimalist theme to replicate the early years of life of Synapse, while the lower ones were destined to house the most scientific settings," explained the older sister, as she and her younger sister walked behind him. "They also served as open-air museums for many plant life now extinct on the Surface."

"There were also talks about housing the animal ones, but it was dropped for lack of space." Continued the younger. "So instead they preserved the DNA so that one day it might be possible to bring them back to life."

"For real?" asked the older. "I didn't know."

"Hehe..." Her sister chuckled. "You need to read more, nee-san."

She chopped her on the head. "I don't want to hear it from someone who still need help with her own maintenance!"

Casshern blinked, unsure as to what make out of this bizarre exchange. He stood up and looked down over the border of the island. "The Surface? You mean Earth? I noticed when flying that I couldn't see it no matter where we go."

"You can't. The same energy field which shield Synapse from the Dow...humans-" The older hastily corrected herself. "-also shield the vision of the planet from here. You need to pass through a portal to see it."

"I see. Thanks...ah." He looked embarrassed. "Forgive me, I was so eager to see Synapse I never thought of asking your names."

"Our names? We are the Harpy sisters!" They declared with pride. "First Generation Interceptor Type, Ambush Class: Type-Gamma, the most loyal guards of Master Reikoku!"

"I am the older one!" The Harpy with light blonde hair declared, eyes closed and an hand over her chest.

"And I am the younger one!" The Harpy with green hair continued, making a pose like a human idol.

Casshern blinked. He blinked again. "Ah, I see...but that is your classifications. How do you call yourself to distinguish from each other?" Now that he looked closer Casshern can see each sister had identical features and honey-colored eyes.

They both opened their mouths to answer. Then suddenly shut it. Opened, and again shut. They appeared bewildered. "W-We don't." The older hesitating said. "There was never any need. I mean, we are always together and we act together. We were always the Harpies."

"Yes, but nee-san: all the other First Generation Angeloids have names. Even some of the Medical Specialist Angeloids do! Why not us?" Interjected the younger. It was a simple question, but it was enough to threaten their worldview.

Not completely understanding but seeing how the two sisters were distressed. He racked his brain thinking for a solution until he was struck by an inspiration. "What if...I give it to you myself?"

"Huh?" They both asked.

"If you don't have names, will it be alright to choose one for you myself?" He repeated. "That's, if you don't want to choose one yourself."

"Uh..." They were dumbfounded, not really knowing how to respond. "I guess it is...alright?" The older sister said. The younger nodded.

"Alright. Now, even if I don't have many memories I should be able to..." Casshern crossed his arms over his chest and began thinking. 'They called themselves Harpy sisters. Harpy...harpies...' Suddenly from the depths of his data banks emerged a couple of names, brought back by terms association. "Aello...and Celaeno." He spoke slowly. "Yes. Aello for you-" He pointed to the older sister. "-and Celaeno for you." He shifted to the younger.

"Aello..." The older repeated, testing how it sounded.

"Celaeno..." The younger did the same, a soft smile slowly forming on her lips.

"That's right. I was thinking about 'Harpy' and suddenly those names came to me. Do you like them?"

"T-they're...nice." The older looked away, a blush spreading on her cheeks.

"Aello! Celaeno! Yay! Now we sound like important people!" The younger cheerful exclaimed. "Don't you think so, Aello nee-san?" She blinked before smiling again. "Wow! It sound so much better when I add a name. Your name. Oh! Aello-neesan, try saying mine! Say mine, please?"

"Urgh..." She looked embarrassed, but nonetheless complied. "Uhm, like: 'How are you doing, Celaeno?', or something like that?"

"Why, I'm doing fine. Thank you Aello-neesan!" Celaeno literally beamed. "And thank to you too, Casshern! This is the best present someone had ever give to us!"

"Uh...yeah, thanks." Aello reluctantly repeated.

"Don't mention it, it was only fair after you did so much for me. Say..." He looked left and right. "Until now we haven't met anybody. Shouldn't Synapse be full of Angels and Angeloids? Where is everyone?"

Hearing the question both sisters stiffened. They nervously looked each other in the eyes before Aello nodded and turned to Casshern. "That...is a bit complicated..."


Later we found the three on another island walking on the paved road of a, by Earth standards, rural town with wooden houses, back gardens and even tree houses. Walking around cleaning and taking care of the plants were numerous Angeloids, all identical in appearance: teenage girls wearing nurse outfits with blue-purplish hair and green eyes. All their faces were blank and didn't reacted in the slight at the group's presence.

"They are Medical Specialist-class Angeloids." Aello replied at Casshern's questioning look. "They have the duty of taking care of all the installations. With low emotional functions and no speaking ability they are more close to a 'robot' that an Angeloid."

"I see..." He appeared a bit troubled but didn't say anything. Instead he changed subject. "What do you want to show me?"

"That." Following Celaeno's stretching finger Casshern could see a more futuristic building, a dome with a bell at the top.

After entering Casshern was greeted with a very astounding sight: inside the artificially enlarged room laid hundreds of capsules, each containing a sleeping Angel.

"This..." Aello hesitated, but continued. "This is by now a common sight on Synapse: all the Angels spend every hour of their time inside the "Dream Avatar System". It lets them create human-shaped bodies on Earth and live life as a human. Once an avatar dies, the dreamer is simply shifted to a new one without need of waking up. They don't even require food. It has been like that...for a long time."

"Why?" Casshern asked touching a pod, likely expecting the one inside, a young boy, to wake up and speak to him. "I can understand wanting to live a different life, but with such a splendid nation why is no-one out enjoying it. Wait, what about Master? He is awake."

"Like us Angeloids, who are immortal as long as we can be repaired, medically science made possible for Angels to never age or become sick. I think...they had become so bored after living for so long that they prefer dreaming and for some time forgetting their real life," Celaeno replied.

"Us Angeloids don't dream and never have a problem with the passage of time, so I can't say I fully understand," Aello continued. "Master Reikoku, as the Sky Master, is duty-bound to be always awake and manage Synapse. Even if he, I can assure you, wishes with all his heart to sleep himself."

Casshern fell into silence for a long time, slowly going from one capsule to another.

"I don't understand," he said at the end, face furrowed in concentration. "I mean, I understand they have to have a reason to sleep for so long, but I can't imagine it. Synapse is such a beautiful place, but almost no one relishes it." He turned to the sisters. "Maybe...the Surface is much better than Synapse? And if it is, what stops them from going there awake?"

"Uhm, the truth is..!" Before they could continue the voice of the Sky Master resonated from their communication channels.

"Casshern. Harpies. Return at once."

"Master is calling. I think it's better if you ask those questions directly to him." Inwardly Aello was glad to have avoided a minefield. Now the Master will answer in her stead.

Casshern nodded and together they made their way back to the Sky Master Temple, leaving behind the sleeping forms of Synapse's masters.

Sleeping, and dreaming.