Prolugue
Fighting. That's how it happened. You were in Levi's squad. There you were,in his squad fighting.
Going in front of Gunter to protect him,you got ready. No one was going to die with you here. The Female titan grabbed you.
Your reactions...They were quick,just not quick enough. She grabbed you buy the leg.
"Y/N!!"Levi yelled.
He rushed over,but it was too late. You were thrown on the grass below. Your efforts were a waste. Gunter died soon after.
Slowly everyone died. Everyone exept for Levi. He chased the titan off. He rushed over to you.
"Y/N! Please wake up!"
He shook you. No jolt or anything. Just a dead corspe in response.
"I promise."
Promise what? You were already dead. There was no point in promising anything. You didn't wan't to be advenged just like Carla Yeager.
Besides,Levi has his whole squad to advenge,and the whole squad includes a lot more than 1 person. Levi also has his own worries. Like Eren. Humanity. Titans. He shouldn't be worried about some dead corspe.
That's when you remembered. You loved Levi. He meant everything. You never got to the confession. That's when you realized that he must gave loved you as well.
"I promise to advenge you. I'll advenge you first."
How? Defeating the Female Titan. Now that's just for Eren. You mean,the female titan is the threat for Eren.
Like he could read your mind,Levi continued,"How? Easy. I'll destroy all titans."
Even without your squad. He was risking his life to advenge you. But you're just a dead person that he showed no emotion whatsoever to.
Still,people can change at the last minute. Right now,it was after the last minute. Four dead souls to take care of.
"I can do it alone without my death."
You trusted Levi with your whole heart. You'll guide him through your vengeance.