This OC is by Yasuno_Kazuhi I hope you like it.
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Name: Shion Nageki

Nice name

-Name Meaning- 
Shion: Aster (Remembrance) 
Nageki: Lamentation

Very interesting

Gender: Male

Nice

Birthdate: Oct. 10

Cool

Classification: Sensor, Medical Nin

Good I haven't seen many medical ninjas and that's great considering that there are tons of ninjas.

-Age- 
Part 1: 12
Part 2: 16
The Last: 19
Boruto: 31

Naruto age group, cool

-Rank-
Part 1: Chunin
Part 2: Anbu
The Last: Anbu
Boruto: Jonin

Wait he was a chunin at 12? He graduated like itachi? Not to mention anbu is after jounin so why do you have it like this, I can understand having a strong OC but he doesn't need to go through the ranks fast.

Graduation Age: 9
Chunin Promotion Age: 11

As I said there ain't nothing wrong with strong characters but you are making him just as strong as Kakashi and Itachi who were way beyond their years.

Village: Konohagakure

Nice

-Family- 
Aoi Ushio (Father, Deceased) 
Hinagiku Nageki (Mother, Deceased) 
Shiro Nageki (Twin Brother, Alive) 
Hisoka Shimura (Foster Father, Alive)

Thanks for the family relationship and life status.

-Appearence- 
Hair Color: Black
Hair Style: straight, ends just above shoulders, bangs are uneven with one strand between eyes
Eye Color: Dark Blue
Skin Tone: Pale

Ok nice

-Outfit- 
[wears headband around neck in Parts 1 and 2. Starts to wear it on forehead in The Last and Boruto]
[wears perserved four-leaf clover charm hidden under shirt]
[tanto sheath diagonal on lower back]

Part 1: dark blue hand made jacket with hood over gray shirt, black pants, black shinobi sandals

Part 2: standard Anbu Uniform, fox mask with blue markings on cheeks

The Last: dark blue kimono jacket with white trimmings over light gray shirt, black pants, black boots

Boruto: navy blue haori that goes down to knees over gray shirt and black pants, plain zori-

These are some pretty nice clothes and I can imagine it a little so good.

Personality (INTP)- 
To most, he is only described as odd. He mostly keeps to himself, and when he is engaged in conversation, it is usually hard to keep track. He has childish interests such as stuffed animals and sweets, though, he is stoic toward everything else. 

To his close friends, he is still odd though more endearing odd. He cares deeply about his friends and family, but he has difficulty expressing his emotions, and it can come off as awkward or forced. Once he opens up, he reveals a sarcastic self-deprecating sense of humor. 

He values honesty, justice, and loyalty above all else. He has difficulty understanding others, and he often thinks too much on that subject.

You know this is a very unique personality, the fact that you make him a odd ball already makes me unique and really shows his characteristics. His likes and everything about him follows this oddness. Beautiful.

Kekkei Genaki: Meiton

Cool

Chakra Nature: Fire

Nice

Tools: Tanto, Dagger, Kunai, Shuriken, Sebon, Explosive Tags

So average, good

Fighting Style: Relies heavily on Kekkei Genkai to absorb enemy chakra, Competent in Kenjutsu and Medical Ninjutsu

Really good

-Backstory- 
The twins never knew their father. In their small home on the outskirts of an unnamed village in the Land of Fire, their mother raised them on her own. Their father had been a shinobi, and he had died on a mission before their mother had known she was pregnant. She was a harsh mother at times, but she was kind and loving. When the two were 5, she began to train them to use their family's kekkei genaki. Hinagiku warned both of her children when they first started training together to not let the villagers see it. During this time, the two were playing in the forset. They created blue flames to throw at each other harmlessly. They didn't know, but a man from the nameless village looked on in horror. That night, the twins were awoken by the sounds of footsteps. Hinagiku was already outside when the twins saw a small mob of people. They all carried a farming tool like a hoe, sickle, etc. and some carried torches. Their mother told them to go back inside. Shion nodded reluctantly and dragged his younger brother inside. The two watched as the villagers held their mother down and beat her. Shiro, unable to control himself, ran to her side. Shion quickly followed. They both knelt by her side, and she smiled before she saw a man with a sickle raise his weapon against her children. She snarled and summoned blue flames as she stood up. She took the blow meant for her children and used her flames to push the other villagers away from her home.Surrounded by flames, the villagers trembled as she glared at them. "Leave," was all she said as they fled. Hinagiku died that night due to her wounds. The twins buried her near their house, and while they kept training, they were very careful not to let anyone see. One day, a man from Konohagakure came to them. He saw their rare kekkei genaki, and he believed it would be better if they used their power as shinobi. The man, Hisoka Shimura, took them under his wing. The two lived in a small, rundown apartment. They were trained harshly by their caretaker, and it left notable scars on both their bodies and minds. Due to the harsh training, the twins both graduated early from the academy and were placed on genin teams very young.

This is a very vivid backstory, it really shows what he been through and so much more. Also thanks for explaining how he got on a team at a young age.

-Jutsu- 
Meiton: Inhaling Maw
Meiton: Judgement
Meiton: Kitsunebi 
[User creates palm sized blue flames around themself. The flames are directed towars the target individually. The target's chakra is absorbed, but the user does not gain it.] 

Very nice jutsus.

Meiton: Phantom Needle 
[The user infuses their chakra into a sebon. The target hit with the sebon has their chakra slowly absorbed by the user. If the user is a sensor, they can track that target much easier than normal.] 
Meiton: Chakra Scalpel 
[The user incorporates the meiton chakra into their chakra scalpel. The user can now absorb the targets chakra on every direct strike.]
Meiton: Soumatou 
[The user blows out a large spinning ball of blue fire towars the target. The inspiration behind this jutsu came from observing the Uchiha clan's fire ball jutsu. With this jutsu, the target's chakra is taken but not absorbed by the user.] 
Sensing Technique
Chakra Levitation Technique 
Healing Technique
Chakra Transfer Technique
Katon: Demon Lanturn
Secret Technique: Phantom Dragon Flame 
[Shion merges his meiton with his katon. He breaths purple flames at the target. These flames act like normal katon techniques, but they also take away the target's chakra. The user inhales to absorb chakra.]

These are all very good, thanks for for explaining them and everything.

-Trivia- 

Favorite Foods: Tricolor Dango and Apples

Nice

Least Favorite: Apple Pie and Peppers

Oh ok

Favorite Word(s): "Justice"

Nice

Wishes to Fight: Higan Nageki
[First leader and founder of their clan clan] 

Cool

Hobbies: Flower arraging, Reading

Sweet
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Final Analysis- This OC is really good and everything is thought out. I was wondering why he was on a team at such a young age but after reading the back story it's justified. Not to mention the fact that he's a medical ninja is just perfect I seen other OCs be medical ninjas but never a male, this is really good. Thank you so much for letting me review your OC, it was a honor.
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