Previously

She was an ADULT.

Eri: MOM!!

She dashed and banged the Cube. Rose searched the place for a switch and found one. She flipped and thr cube dispersed, Finally freeing Eri from her Prison.

The two ran to each other and hugged. Eri was crying, happy to be free and to see her Mother.

Rose: Come on now Eri. Let's get your Father and go home.

Eri: Okay.

The two went outside. But was beyond shocked to see only Issei celebrating.

Issei: I killed him! I finally killed him! Finally!

He ran off before Rose can do a thing as she broke down crying now that she lost her Husband. So did Eri.
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Somewhere else
3rd POV

In a far away place. A Great Seer is looking through the future as a person is, wanting to know Earth's Future.

Seer: I see......Danger....Danger from Extraterrestrials!!

The man wrote it down and ran off.
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in space

A person has landed on a planet devoid of Life, But Abundant of Nature. He looked around and saw a Girl, standing on a Tree.

Girl: You have shown yourself boy.

And now

The Entire Family, consisting of Rose, Pneuma, Genesis, Gabriel, Eri, Nezuko, and Rose's Parents were in a dark mood to say the least.

They lost the man they called Husband, Son, And Father.

Rose was distant, Very distant to everyone else. She would just prepare her Kids for school before isolating herself.

Pneuma had an Aura of Vengeance, Bloodlust, and Hate. She is determined to find the pervert and torture him till the end of his days.

Genesis was almost the same as Pneuma. Just less Bloodlust.

Gabriel was also very distant, Rarely coming back from her Angel duties.

Eri and Nezuko, When they heard the news, They were crying, hoping that it was joke, but it never was. The two's grades in school has dropped slightly and falling.

Iri was crying after seeing her Daughter lose the Perfect Man for him.

Vorzechs is exactly the same as Pneuma. Just more Vengeful. Everyday, He's been incinerating Dummies, Dismembering them, and Throwing knives at a Picture of Issei.

Vorzechs is determined to have vengeance. And so does her Daughter aswell.

3rd POV
Present Time
Eri and Nezuko's School

Eri and Nezuko, whom just came from School, was still sad after their Father's Death. The principal understood that an Incident occured and hence why Eri is an Adult.

When the two came back, Eri finished only half her assignments before going outside to train her Martial Arts. She has been been like this for a Full week ever since Y/n died.

She has been trying to perfect one of two Martial Arts. It's called "Fist of Flowing Water, Crushing Rock".

It's fighting style that specialiIng in repeling the attacks of their opponents, nullify them, or redirect them with twice the power. A Perfect blend of Offense and Defense.

She used a simulation and used a Haptic Bootsuit to feel the pain and force. Everytime the enemy hologram punches, Eri deliberately takes the hit and tries to redirect it.

Day by day, Night by Night. She just won't stop, She's just tiring herself to the brink of collapse. Good thing Rose and Nezuko was able to halt it and make her Rest for the day.

The next day

Eri and Nezuko were preparing for School. Rose still has that Depressing aura around her, Same goes for Pneuma.

The two put on their uniforms and went out after kissing their Moms goodbye. When they left, The two isolated themselves.

The school was just a 10 minute walk from their House, And they, themselves wanted to do so, as they are strong enough to protect themselves.

The two weren't half as lively as they were, Now that They lost their father.

Eri: Hey Sis? You go on ahead. I'll....Catch up later.

Nezuko: Are you sure? You'll miss school.

Eri: I'm sure.

Eri wandered off the nearest Park and sat there, Thinking. Now her Father is gone, She is wondering what her Family's Mood are. Even if they get happy, It'll just be futile as Y/n is mostly the one that brings them happiness.

*BOOM*

An explosion was set off nearby. Eri turned to the source and it was Ruins. Buildings destroyed, Small craters, and scattered debris.

The most noticable that in the center, A giant Villain was there. Gigantomachia, One of All for One's Servants.

Gigantomachia: Come out All might!!

All might? What does it want with him. Eri dropped her school bag, and activated the Gate of Wind for Speed.

The moment she got there, She saw three more figures. A Man with some sort of Hand feitsh with how many hands he has on his body, All for One, And the Symbol of Peace, All might.

All for One: You're weaker than before. What's wrong All might..

All might: *mind* Damnit. I can't win against all Three of them. And delaying is out of the question, I only have 30 minutes left. That may not be enough.

All might charged at them while firing Air blasts. Shigaraki dodges every singlen one while AFO responded with Air cannons.

All might was about to punch Shigaraki, but Gigantomachia shielded it with his body and a Shock Absorbtion quirk.

Gigantomachia created an Earthquake by punching the ground, which pushes All might back.

All might: *mind* Damnit. I can't even get close to one. I need help.

Eri was able to get to All might while having Wind Gate open. She took her stance and prepared a New Attack. All might was barely able to keep up with her.

Eri: Sekizo! First step!

Eri punched an Air cannon to Shigaraki, But Gigantomachia shielded him again, but the Behemoth was too slow, as Eri has already got behind them.

Eri: Second Step!

The Air cannon launched Shigaraki into Gigantomachia's Back, Knocking him out and injuring his Back.

AFO: What the?!

Eri: Third step! Fourth step!

2 more Air blasts were directed at each concious Villain. All for one was barely affected while the Big guy just staggered.

Eri: Fifth Step! Machine Gun Blows!

This time, Eri fired Several Air blasts at the Big guy. But AFO responded with his own, Cancelling each other. Eri returned to All Might's Side.

All Might: Young Lady, What are you doing? This is too dangerous for you!

Eri: The Pro Heroes are too far away to help you. And you're struggling to fight the 3, So I helped.

All might: *mind* She's right. I can't even get close enough. *out-loud* B-but, Why are you helping? Even if you live, You may get praised, but You'll get arrested for Power Usage.

Eri: Praised? I remember the True Definition of Hero. One who saves Lives, No matter the cost, Even if it costs their lives. Doesn't matter if I get praised or not, I'll be a Hero, even in secret.

"I wanna be the Saikyou Hero"

All might was shocked at the small speech of hers. But He can't help but agree. That was the reason why he became a Hero in the first place, To save Lives and become the Symbol of Peace. He regained the Smile on his face and accepted.

All Might: Hehe. You got bravery Young Lady.

Eri: Let's save it for later. Right now, We have Villains to deal with.

The two took their stance as All for one just laughed.

AFO: Do not think having a Little girl helping you will do any good Yagi.

Eri: I'll take on the Big guy. You'll get their Leader.

All Might: Are you sure about that Young Lady?

Eri: Gate of Fire, Open! And my name is not Young Lady, It's Eri L/n, Or aka, Might Girl.

(Cue "You say Run")

Eri's Eyes glowed a bit before she dashed towards Gigantomachia with Fiery Hands.

Gigantomachia raised his hands as Claws appear.

Eri: Firestorm

She raised her hands and fired Fire blasts at High Hea at him at Immense Speeds.

Gigantomachia was sweating from the Burn as Burn marks appear on his body. Eri speed up infront of him and jumped.

Eri: Gate of Earth, Open. Machine Gun Blows

Eri's fists were infused with Earth Powers before punching at blinding speeds.

His Tough Hide/Carpace is starting to break, But the Shock Absorbtion was doing work on the Force.

Gigantomachia: Lowly animal!

He slashed towards her with his Claws, But she barely dodged away as some part of her clothing was torn.

Eri: *mind* Gotta end this quick.

She fall backed a bit to All might's side, Whom the latter was struggling to keep up with All for one.

AFO: I will commend the Little girl for her Power and Courage. But this ends now. I'll hit you with the Ultimate combination of Quirks at my Disposal.

AFO's Hand starts to enlargen and get armored by the quirks. While Gigantomachia was growing in size.

Eri: GATE OF GAIA, OPEN!

Eri's eyes loses their irises and pupils as her Hair flew upwards as she took her stance, To be exact, Night girl.

All Might: To overcome the crisis infront of you.

Eri: By giving everything you've got!

All Might: And save people.

Eri: No matter the cost!

The two then dashed at their respective opponent with Heroic Intent. Both Villains were readying to fists/Claws.

All Might: That's what make someone!

Eri: A True Hero!

AFO: TIME TO PUT AN END TO THIS NONSENSE!

As the Hero and Heroine were nearing their opponent, They shouted a Name they will never forget.

All Might/Eri: UNITED STATES OF SMASH/NIGHT GIRL!!

The fists collided with the villains in a Clash. They were equal in Power, But the Heroes were not done Yet as Eri's Fiery Aura magnified and All Might had a Silohouette of every Hero behind him.

Eri: LET'S GO!!

All Might: BEYOND!!

Both: PLUS ULTRA!!!!!

Their Punching Power magnified, Easily overpowering their Enemy before hitting their Chest area and smashing them to the ground.

The Immense Force and Power created a Massive Crater and a Massive Tornado.

The moment they were done. The two raised their Fists victoriously while a News Helicopter was broadcasting everything.

Reporter: That was....*wipes tears of joy* the Mightiest Battle.

To be continued

Next time

Who are you?