Board Thread:Manga/@comment-30064439-20161113032209/@comment-5179916-20171205164528

For me, it's always been Annie.

Eren and Annie have a bond that no one else comes close to having, not even Eren and Mikasa. As mentioned by others,  Eren is the only one who has made Annie genuinely smile and as trainees the two had a mentor/student relationship, sparring together numerous times as she taught him her father's fighting techniques. Also she is the only one out of the three Warriors he doesn't show rage and anger over in regards to the Paradis Island Operation. Possibly the biggest piece of evidence is that while Annie ignored or didn't react to anyone's goals & desires (not even her fellow Warriors), Eren was the sole exception. They both strive for a specific goal in life and never veer away from wanting to achieve it and both want to break free from their respective 'chains' (Eren's desire to not live his entire life shackled within the confines of the Walls and Annie's desire to  return to her father and  live a normal life instead of one based purely on servitude to Marley).

I know most people want to pair Eren with Mikasa. Due to them being all the other has left now,  Mikasa and Eren are always together and after all the constant struggles they've faced together, many would say they are inseperable. However, he is annoyed that Mikasa is too protective of him and still treats him like a child. Also,  she has been Eren's 'sister' for so long that he probably only sees her as a sibling as opposed to how Mikasa sees him as being more than that.

I know it's up to Hajime Isayama but if he does decide to ship Eren with someone, I think it will be something done quietly just between the two characters with no one else knowing. In my opinion, both Eren and Annie have reached that point and understanding between each other