Board Thread:Manga/@comment-27321453-20180708204808/@comment-1327106-20180714045803

Eren x Historia starts during the Uprising arc though. He's the only male member of the 104th who sees her for who she is and prefers that person (Chapter 54). This is actually the first heart-to-heart conversation Eren has with a girl his own age. It's not his heart, but Historia really opens herself up to him and he's accepting of it.

Chapter 70 has the two of them bonding further. Eren calls her amazing and Historia blushes, and then Mikasa butts in (of course) before anything further can happen.

The seeds were planted. It's just they've been dormant because she couldn't participate in the Battle for Shiganshina and much of the Marley arc.