I don't want anyone else to end up like me! I want free those who had their freedom taken away, and eliminate those responsible! I want to show the rest of the humans that I'm worthy of being in their presence! So please, Master, train me! I want to be a shinobi!

–Aoi Fen Yu, Begging Arashi to train her.

Aoi Fen Yu


Mermaid (Siren)

Age (TS)


Age (AA)


Eye Colour


Hair Colour




Kill Count


Aoi is a Mermaid (better known as a Siren, due to her powers) roleplayed by Derp on World 42, in the Ancient Alliance and Tenkaze Shinobi sandbox role-plays.

In her early years, she was a member of the Tenkaze Shinobi.  Later on in her life, she became a wise Mystic, and the sensei of Takeo Kuroshima, the retired Death Lotus Assassin.


Aoi has a face structure much like that of a human, and she has a rather pretty one; something rare among mermaids. She resembles a shark, most of all, and she has rows of jagged, sharp teeth and pointed ears. Her eyes are almost a completely solid black, with a thin strip of dark greyish-blue around the edges. Like a shark, her skin is a pale shade of grey, almost nearing white. She has darker greyish-blue, tattoo-like strips around the left side of her body, including her arm, side, and abdomen; these strips envelop her entire back. She has quite a bit of muscle on her, but still has a smaller build; she weighs 58kg, and stands at 5'6" tall with her legs. With her tail and fins, she measures 7'6" in length. In her natural form, the upper part of her tail is dark, like the skin on the left side of her body and back.  Her tail also rough scales that act as a natural defence, like what sharks have in real life.


In her early years, Aoi was quiet and respectful; due to her past as a slave.  After she joined the Tenkaze Shinobi and began working to become a Mystic and Arcanist, she became more outgoing and wise, on top of her quiet respectfulness.  For her whole life, since she was young, she's had a desire to prove her worth to humans that think of her as less than human, and become the best that she can possibly be.  While she never exactly enjoyed killing people, her experiences gave her an incredible knowledge of life and death in her later years, which made her an even greater sensei. 

Armament and Armour

As a shinobi, Aoi is experienced with many different kinds of weaponry, ranging from swords to handheld explosives.


Aoi's thighs are armoured on the front and sides by her haidate; constructed from many small, iron and hard leather plates connected by lace and rivets.  Her suneate (or shin guards) are constructed from iron plates, attached to leather and held together by small hinges.  Her pants are made so that all the armour can come off with the pants in one piece, so that she can remove them quickly, as she is a mermaid and can't transform her legs in to a tail with pants on.  Her torso is simply clothed with a revealing, leather top.  Aoi was never too big on wearing clothes.

Melee Weapons


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Aoi's kodachi.

Aoi's kodachi was forged from steel by an experienced blacksmith.  Its blade measures 17 inches in length, with a 6 inch hilt; in total, being just under 2 feet long.  It is carried in a saya that rests horizontally across the back of her waist.


Aoi wears two steel kakute on each hand, facing outwards.  When unarmed, she will sometimes turn them inwards, to allow her deliver painful grabs in hand to hand combat.

Ranged Weapons


Aoi carries five hira-shuriken and three bo-shuriken in leg pouches.  They are all made out of steel.


Small objects such as hollowed-out egg shells, clay spheres, or paper bags containing sand and glass used to blind an opponent.  Aoi often carries a number of these devices with her on missions.


Grappling hook

A rope connected to a two-pronged metal hook used to catch tree limbs or the sides of buildings and climb.


Metal bands and prongs worn on the bottom of feet and the palms of hands to allow the wearer to climb up a steep surface. The palm prongs can also be used to block blade attacks.  She does not always carry this gear with her.


A small, iron utility knife.  It can make for a decent weapon in a pinch, which Aoi makes uses it for often.


Siren Gifts

Aoi is a siren, and she possesses a voice capable of singing people in to states of hypnosis, where she can take advantage of them; her voice can also be used to command sea creatures.  She also has the ability to travel through the water very quickly using her natural form, and is capable of manipulating water at an expert level, naturally.  Her bones and muscles are stronger than those of a normal human due to her childhood under the pressure of the ocean, and the underwater training she does.


Mystic Powers

Martial Arts and Swordsmanship


Early Life

Aoi Fen Yu was born in The Sunlit Veil, rather, in the water around it. She doesn't have much memory of her loved ones, as she was taken away from them by the daring western "Black Morning" pirates, when she was only 4 years old. The Black Morning pirates sold her in to slavery for a large sum of money in the black markets of New Heritage. From there, she was picked up by a noble as a birthday present for the Khan of Echo Bay. The Khan of Echo Bay was a terrible, violent man who abused his servants and subjects; Aoi was no exception. She was mostly used for decoration in the Khan's fish tank when she was younger. Here, Aoi befriended an older Siren named Kaiyo Tsuma. She taught her how to use her mermaid abilities in secret. When Aoi became older, around 13, she began doing work for the Khan outside of the fish tank, along with Kaiyo. The defining moment in their relationship was when the Khan forced Aoi and Kaiyo to have an underwater fight to the death as a show for his friends while he hosted a party. Kaiyo, not wanting to put her "daughter", Aoi, through the act of killing her, committed suicide. The Khan was enraged for being embarrassed in front of his guests, and he ordered Aoi to be executed for "poisoning" Kaiyo's mind. On the day of her execution, Aoi marched up to the gallows, singing a song that her and Kaiyo used to sing together. Her mermaid abilities took an effect on the song, and hypnotized the entire courtyard, including the guards. She escaped from the Khan using her new powers.  For weeks, she swam across the ocean, braving the harsh conditions and violent creatures that wandered the depths of the Eastern Sea. Tired, and lonely, Aoi lost the will to live, and simply drifted across the sea in a comatose state, until she washed upon the beach of Tsurusen, home of the Tenkaze Shinobi.

Tenkaze Shinobi

Becoming a Shinobi

Aoi was discovered on a beach outside the Tenkaze Village by Kazemaru, Tuyen, and Chun.  She had been wounded by a shark while adrift among the ocean, and they took her in to receive medical treatment.  When Aoi awoke, she was scared, especially since everyone was human.  She tried to escape, but fell down from her wounds, and she was 'forced' to receive treatment.  The following morning, she was woken by Kazemaru, who was checking to see if her condition had improved; while shy at first, Aoi eventually opened up to him, and agreed to see the leader of the Tenkaze Shinobi, Master Arashi.  Since Aoi had nowhere to go, Arashi offered to let Aoi stay in the village if she worked, but she insisted that she had no skills.  Kazemaru kept suggesting to Arashi to make her a shinobi, but Arashi said it was her choice.  After being told to think about what she wanted to do, Aoi suddenly burst out, begging on her knees for Arashi to train her so that she could make the world a better place, where others wouldn't share the same life that she used to live.  The following morning, she began her intensive, month-long training.

Misson 1: The Western Slavers

For her initiation mission, Aoi was tasked with eliminating a band of slavers preying on whole villages, led by westerner named Asahd Dumar.  The slavers were being funded by Takashi Asahiro.  Upon reaching the village that the slavers were abducting people from, Aoi ran in to Kazemaru, who had been scouting the village out.  He reported to her that it was cleared of all civilians, and that only six slavers remained in the village, while the rest were on their ship with the villagers.  Kazemaru left Aoi to her first mission.  She climbed across the rooftops of the village and dropped down on the first guard, ramming her kodachi through his neck.  She proceeded, getting back on to the rooftops.  She came across two more slavers talking loudly next to a well.  Using water magic she created a distraction with the water at the bottom of the well.  She used this to drop down, behind the slavers and slice the top off of one of their heads, and slit the throat of the other.  The sound of her dumping their bodies down the well attracted the attention of a fourth slaver, who came outside, only to have his head lopped off with a hira-shuriken and wind spell combo.  Aoi took his crossbow, along with three bolts; she ran to the front gate, where she eliminated a slaver guard by shooting him through the head with the crossbow.  After climbing the village wall, she shot another slaver through the head below her, and jumped down in to the water by the pier.  Removing her top, she began using her magic singing voice and female charm to lure one of the slavers in to the water, where she dragged him down and ripped out his throat with her powerful jaws.  She then reloaded the crossbow underwater, and ascended, firing the last bolt in to another slavers head, who proceeded to fall in to the ocean.  Aoi climbed the outside of the pier and jumped on to the side of the large slaver ship, climbing through a cannon port.  Inside the ship, Aoi found Asahd, and tried to sneak up behind him; she failed to deliver a stealthy death to him, as he blocked her kodachi.  The two exchanged a flurry of strikes, and Aoi sliced the tendons in both of Asahd's forearms.  As he attempted to retreat and hit Aoi with some sort of magical spell from his mouth, Aoi blinded him with a metsubishi and blew up his torso with a cannon that she had aimed towards him.  After killing Asahd, Kazemaru showed up on the ship; Aoi sensed a surprise attack from the remaining slavers on the boat, and sure enough, they were assaulted by eight slavers dressed as prisoners.  Aoi fought off four of them by herself, gruesomely downing each of them with her kodachi; finally, she killed the last one, ramming a kunai in to his stomach while he jumped at her, slamming him on to the ground and stabbing her kodachi through his shoulder and in to his heart.  She then threw a bo-shuriken through the head of the last slaver that Kazemaru was fighting.  Before leaving, she went in to the hold of the ship to see the villagers.  A few of the young children were dead, and the rest cowered in fear.  Aoi was overwhelmed by the similarities between what she saw, and her past, causing her to bust in to tears.  Kazemaru comforted her, and they both teleported back to Tsurusen.  Overall, her first mission was a success.

Mission 2: Temple Shadows

Both Aoi and Kazemaru were sent to investigate the temple on Tuai Leit that Asahiro's funds were going to and Innen was frequently visiting, according to Kazemaru's scout work. When the two ninja made it to the surrounding swamps, Kazemaru caught a glimpse of Innen and chased after him while Aoi delved into the temple's catacombs. Inside, she discovered that the temple's monks were being brainwashed and their bodies mutated into vile, cannibalistic, horrifying monsters. Aoi braved the hellish catacombs and freed the remaining monks from the grasp of a madman clutching a crystal shard that held control over them, killing the madman and destroying the crystal.

As Aoi exited the catacombs, she saw Kazemaru as he was easily defeated by Innen himself. Using illusions, the ghoulish man tricked Aoi into stabbing Kazemaru through his abdomen. Before Aoi could exact her vengeance upon Innen, he escaped with Kazemaru's body. The village mourns as Kazemaru is presumed dead.

Facts and Musical Inspiration

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