This whole chap's gonna be in Third P.O.V. Sorry it came out so late. Writer's block's no joke man. In this chap we'll get some backstory on the Evans and (Y/N) herself.

(Y/N) Evans. Born to the Evans household, in Wall Sina.
Her parents Estelle and George Evans belonged to the Survey Corps since they were young, and rumor was it they were childhood friends of Erwin Smith himself.

The Evans were an old family from Wall Sina; rich, noble, and famous-though those details have long been forgotten. In their time of rising they became powerful by helping invent ways of attacking the titans and supporting the creation of the Army and the subdivisions: the Survey Corps, the Military Police, and the Garrison. It was even said that they knew the king himself.

However, that changed when the blood line went to Estelle Evans' parents. Their influence died a bit because of bad business choices and actions. Estelle tried to repair the damage her parents had caused to the family's name, but couldn't.
She married George Sparrow, a merchant in hopes that they could both help each other in the business, even it they were both too young. In the end, they left work and became part of the Survey Corps, quickly rising in the ranks.

When their daughter was born, they didn't have enough time in their hands to take care of her and their businesses-which were pretty much dead alredy-and they decided to leave the luxury of Wall Sina, and live in Wall Maria.

(Y/N) Evans grew up knowing nothing about her true lineage or the fact that they came from Sina. She thought the only thing special about her last name, was that it was also the strongest soldiers' last name.
As her parents raised in ranks, they were offered to go back to Sina, where they could be safe. But they declined the offer with dignity, declaring that 'We shall not be as stupid and arrogant as the rest are. The walls will fall eventually.'

As a child, (Y/N) grew up getting constant visits from Erwin Smith-and some years later-and Levi Ackerman. The men used to play with her-Erwin more than Levi-and teach her stuff about the world they saw outside. For her, it wasn't strange at all to see Levi and Erwin sitting in front of her smiling, if only slightly. When she was small, around six years old, and she went out to play outside, she was alone. The other kids either didn't dare go near her or were jealous of her for being an Evans and knowing Erwin and Levi. She was beaten up often, to the point her baby teeth fell quickly.
Her parents, of course noticed and decided to teach their girl how to defend herself. They taught her martial arts and basic combat stances and actions. Though she was a little girl, she learned quickly and had astounding strength for her age.

When she was eight... (Y/N) lost her parents. They were away on a mission with the Survey Corps to capture titans to test on. But they didn't make it. According to Erwin Smith, they had been kicked off their horses, dying inmeaditely, and then their bodies were torn apart.
*#
Little (Y/N) was sitting on the chair, waiting for her parents to return. She was humming a tune as she ate mashed potatoes. I hope mommy and daddy return today.

There was a knock on her door.

She jumped up from her seat, thinking it was her parents. Her little feet pattered as she ran to the door and slammed it open. "Mommy! Daddy!" She exclaimed, about to hug the person with a big grin on her face. But she stopped abruptly when she saw her blonde uncle with a grim expression on his face, carrying a folded green cloth. Her (E/C) eyes widened and she could only stare in shock. She understood inmeaditely what was wrong.
"M-mommy? D-daddy?" She called hesitantly with a broken voice.

Erwin shook his head sadly and frowned, handing her the capes. (Y/N) took the bloody capes from his arms with wide glossy eyes.

Erwin looked at her and grabbed her, pulling her into a hug. "I'm so sorry sweetie..."

(Y/N) was never the same again. She ran away from her house a few days after that, and spent some months on the streets. That's when Armin's Grandpa found her and took her in. He asked who she was.
*#

Armin's grandpa sat her down and went to grab a towel to clean up the girl's face.
She sat with a gloomy expression, eyes dull and void of emotions. Her clothes consisted of what looked like it used to be a blue dress, but could only resemble a ragged dirty cloth now, and two capes wrapped tightly around her neck that were dirtied up, signaling she had probably used them as blankets when sleeping on the streets. Her hair was messy, it looked like it hadn't been washed or brushed in a while.

She sat in the humble kitchen of Armin's house, barely moving. The house was small, but it still looked comfy and cozy.

Grandpa got back with a damp towel and gently wiped the dirt off her face. He was a bit taken aback when the little girl's eyes looked at him and stared right into his soul; those flaring (E/C) eyes that burned with rage and sorrow. "Hey little girl, what's your name?" He asked softly, kneeling in front of the chair. His old voice seemed gentle.

The little girl answered with a raspy voice that had probably not been used in a while. "....I-I'm....(Y/N)...."

The old man smiled gently a bit, his beard rising up with his cheeks. "Well, (Y/N), can you tell me your last name?"

The girl frowned and her lips quivered, her dull eyes finally showing some emotion. "E-Evans...."

The old man's eyes widened. So this is that lost girl... Captain Erwin has been looking for her..there are missing posters with her picture everywhere... He meditated on what to do for a moment. This little girl is surely aware that she's been looked for. If she hasn't revealed herself that means.... He furrowed his brows and looked up at the girl again, smiling. "Well, (Y/N), would you like to live with me? I have a grandson, I'm sure you won't feel lonely. He's really kind and nice." He offered gently, offering her a wrinkled hand.
The little girl's eyes widened and her once dull (E/C) orbs lit up with light. H-he's offering me a home?! Seriously?! "O-o-okay. But I don't want anyone to know my last name..." She said quietly with glossy eyes and a small smile.
The old man smiled. Good. "Sure, but call me Grandpa."

After that, (Y/N) Evans started living with the Arlerts and her last name became forgotten, the fact that the Evans' child was missing was forgotten, and she became (Y/N) Arlert. She was a bit cold at first with Armin and his friends, but their happiness and cheerfulness slowly got to her, and she warmed up to them. She slowly turned into a happy almost-teen that was badass as hell. She hated the titans for what had happened to her parents and wanted to join the Survey Corps when old enough to replace her parents and avenge them. She recalled as a little girl, she always had had the feeling that she had forgotten something important. Something that happened before her parents' died. But, who knows what it was.

~><>Now, back to the present. (Y/N)'s dream. Or is it a nightmare?<><~

(Y/N)'s mind was asleep, trapped in a coma, as her body was covered by her titan form. In the back of her mind, she knew it wasn't real. But she didn't have the strength to push away the opportunity of seeing her mom once more.

In her dream, she was playing with her wood dolls and cars, sitting on the floor. She giggled happily as a five year old, moving around her dolls and giving them voices of their own.

Her mom sat on a chair, observing her with soft green eyes. Her (H/C) hair was tied up in a messy bun, and she wore a white apron over her sapphire blue dress. She hummed a soft melody that seemed to calm (Y/N) down, and deepen her slumber. "Hey little girl did you know? Your mommy is here to protect you. Hey little girl did you know? Your mommy is here to teach you. Hey little girl did you know?...." The lyrics went on, varying the phrases and repeating some.

(Y/N) played with her toys absent-mindedly. Yeah... This is my home... Why would I ever want to leave this place? Join the Survey Corps like uncle Erwin? Yeah right, why? If I can stay home here, with my mom and dad.

There was a knock on the wooden door. Little-dream-(Y/N) jumped up to open the door. She tilted her head when she saw a blonde boy on the other side.

His voice sounded muffled, as if he was far far faaaaar away. "(Y/N)!...hav....wake....Please!"

She tilted her head at him confused. Who is he? He seems familiar? She stared at the blonde boy with beautiful blue eyes. He kept banging on something, as if there was glass in front of him that needed to be broken. Her (E/C) stared at him intensely. She felt a tingling sensation, like a thorn stuck in her mind, pricking her, trying to make her see something. Blue eyes?..... Blonde.....

The little girl closed her eyes, listening to the boy's voice. "(Y/N)!... Wake up! Whatever you are seeing! It's not real! I'm real!"

The tingling sensation increased, and her ears twitched. Blonde hair..... What was his name?... I've seen him somewhere...

"....."
"(Y/N), remember what you said to me, when I showed you that book?" The boy paused, pressing his hands onto whatever invisible glass was in front of him.

(Y/N)'s eyes fluttered, as an image came to her; and old book written in brown reddish ink, depicting oceans and snow.

"You said... 'Armin, we're going to the ocean. And we're conquering all of it.' You want to see the world outside right?! So wake up!"

The sentence triggered the splinter in her mind and all her memories rushed back into her; her parents dying, Maria's Fall, training, Eren's and hers transformations, etc. Her (E/C) eyes opened and inmeaditely, the scenery and her house burned down, as her mother screamed. Her body returned back to its age and she furrowed her brows. "Right! Armin! I remember you! And I... I!" She yelled. She made a grab for his pale hand, shattering the invisible wall between them. "Let's do this!"

~><><><~

She woke up inside the titan's neck, snapping her eyes open. She furrowed her brows determinedly. I'm gonna control the heck out of this thing! She closed her eyes, and when she opened them again, she saw through her titan's eyes.

She felt a slight pressure on her shoulder and saw a smiling Armin.
"(Y/N)... Let's do this!"

She roared in approval, Eren's titan form beside her joining in.