In an Alternate Reality IV

Reunion

The Squad watched as Armin obliterated the Founding Titan. The Founder fell to the ground as the explosion disintegrated its bones. All their eyes widened as fierce gusts of wind blew and as they watched all the Colossal Titans fade away with the wind.

"Eren..." Jean said.

Falco descended as the wind grew too fierce. They could all fall or crash headfirst into the ground. Falco landed on the ground, and they all got off the Jaw.

The crowd of Marlyeans and Eldians ran toward their saviors. The Squad slowly turned around as the crowd surrounded them. Gabi's eyes widened as she saw her parents running up to her.

"Mom! Dad!" That was all Gabi managed to say before her parents engulfed her in a hug. Mikasa felt a faint smile grow as she watched the child.

Pieck looked around and she saw her dad. She ran toward him with her arms extended and the two hugged. Then there was Annie, she looked around in the hopes that maybe she might see her father after 9 years of not seeing him.

She vigorously searched until she saw him with a rifle in his hand. Like the others, she ran at him and hugged him tightly.

As the Reunion happened, Falco got out of his Titans with Reiner's help. 

"How are you feeling, Falco?" Reiner asked.

"I'm fine..." Falco said then looked down.

"Did we do the right thing? I mean, after everything I've heard about Mr. Jaeger. And after how he spared both Gabi and I, I can't help but feel bad. He seemed like a nice man." Falco said.

"We did the right thing. Look... It was because of us that these people were spared...Eren was honestly either the best person you could meet or the worst."

"Reiner!" someone in the crowd shouted. Reiner looked back and his eyes widened.

"Mom..."

Karina, Reiner's mom walked toward him at a fast pace and hugged him.

"I'm sorry, son...All this time, I've used you as a tool for vengeance." Karina apologized. Reiner didn't say a thing. He simply tightened the hug as his mother wept.

The Squad just looked at the families reunited. They all then looked back to where the Founder used to be. Armin's Colossal Titan completely wiped it out.

"Damn it...." Levi muttered.

"That brat...He did all this for us." 

Hanji was right beside him and she looked down. The others too looked down except for Mikasa who didn't look sad.

"Eren...I'll see you back home."

-

Eren and Other Eren walked around the Titan Realm. It was all over now; it was time for some explaining. Other Eren began explaining everything to Eren.

(To avoid confusion, Other Eren is the cannon version while Eren is the one in this book.)

"Let's start at the beginning..." Other Eren started off.

"This story first started over 100 years ago in your time when I used to walk the earth from which this all stems from. I too did the Rumbling. Like how I've told you before, I destroyed 80% of the world's population to allow my friends to live long, peaceful lives..."

"The Rumbling's purpose wasn't only to give my friends peace, but to rid off the Titan Powers and the Curse of Ymir."

"Curse of Ymir?" Eren asked.