Soulmates (Levi x Reader)

                                    

                                          
Author's note: This story contains spoilers for season 4, specifically chapter 125 of the manga. You have been warned. [insert spooky laugh here]
                          


                          
You were different from every other soldier in the Scouting Legion. For your entire life, you had been able to see souls.

                          
Souls were breathtaking and unlike anything else on Earth. They sat in the center of a person's chest and were shaped like a tiny flame – one you could hold in your palm. Each person's soul was unique, their appearance being a physical representation of that person's character. Most souls were beautiful, but even the uglier souls usually had some redeeming quality. As you grew up, you realized that this was because most people weren't wholly bad or wholly good; they were somewhere in between.
                          
Most of the time, you were happy that you could see souls. However, after you joined the Scouts, you found yourself wishing more and more that you couldn't. Because whenever you watched a comrade die, you had to watch their soul die, too. Seeing those tiny lights fade into nothing...it added a whole new layer of sadness to the end of a life. Thus, your comrades' deaths affected you more greatly than most other soldiers. You did your best to hide it, though. After all, you had to stay strong for everyone who was still alive and fighting.
                          
This was probably the reason why you had become close with Humanity's Strongest Soldier. Even though he couldn't see souls, Captain Levi still felt the pain of his comrades' deaths very deeply. But like you, he stayed strong. He never dropped his stoic mask, even when the burden was too great to bear. The two of you developed an understanding through your shared grief. While that was the start of your friendship, in time, you were thankfully able to bond over a lot more than that.
                          
Once, Levi asked you what his soul looked like. You told him. It was a soft, pure white, and it had wings. It was the most beautiful soul you had ever seen.
                          
Levi didn't believe you. After his crimes in the Underground City, and after so many soldiers' deaths that he felt responsible for, he expected his soul to be tainted. Filthy. Repulsive.
                          
It took a lot of effort on your part to convince him that you were telling the truth. Throughout his life, Levi had been faced with too many hard choices – sometimes, impossible choices. But that didn't make him a bad person. 
                          
However, there was one thing about Levi's soul that you intentionally did not tell him. Attached to his white flame was a thin, red thread – almost invisible to the eye. And that thread connected his soul to your own. 
                          
You knew enough by now to realize that this meant Levi was your soulmate. You also knew that Levi didn't want to have a romantic relationship with anyone. For Scouts, there was so much uncertainty. None of you could promise a future, or even tomorrow. Levi didn't want to get involved with someone, only to die and cause them pain. He also didn't want to give his heart to someone and then have to endure losing them.
                          
Perhaps, if humanity really did beat the titans one day, and both of you were still alive when it happened, then you would tell him. As things were, you didn't want Levi to feel any more pain than he already would if you died. You loved him too much for that.
                          
So the two of you stayed friends, year after year. Humanity did actually manage to beat the titans, but as soon as that happened, you were faced with another enemy. As your small island prepared to go to war with the world, you still couldn't bear to tell Levi about that red thread. You still couldn't promise him that you wouldn't die.
                          
You were riding your horse through the forest, going to join Levi as he guarded Zeke Jaeger. As you galloped along, you constantly glanced around you out of habit. But there were only trees, and more trees, and Hanji, and more trees...