You might think Rem is the better choice, but from “who’s” point of view?
Ever since the beginning of Re:Zero when Subaru’s transported to “another world”, Emilia is the first girl he talks to.
During the 45 minute first episode, they develop somewhat of a relationship. And he gets to know her pretty well in that short time.
And after watching her get killed, Subaru’s affection for Emilia becomes even more serious than before.
In fact it’s the driving force behind why he’s so motivated to help her initially.
Just look at his expression.
Fast forward from here, Subaru is seen:
- Crying on Emilia’s lap (in the castle).
- Fighting by her side (making their bond stronger).
- And too many things I won’t mention because of spoilers.
While it’s true that Rem and Subaru have emotional moments together, you have to keep in mind: these moments are MORE emotional for REM, not Subaru.
In comparison to Subaru, Rem is “love sick”.
Rem and Subaru’s relationship didn’t exactly start off on good terms… From the beginning Rem was shady, dishonest and even went out her way to kill Subaru based on nothing but assumptions.
She felt no remorse and even went against the word of Emilia.
All in all, Emilia was there from the beginning, and Subaru’s reasons have always been pure when it comes to Emilia. Unlike Rem.
There was never any doubts, setbacks or anything like that with Emilia.
So it shouldn’t be a surprise why Subaru chooses Emilia… literally everything (most of) Subaru does is because of the kindness and compassion Emilia shown him in the beginning.
Emilia is his main “motivation” for wanting to live, help others when he’s able, and of course, to do whatever it takes to protect her.
As far as personality goes, Emilia is a better match anyway.
That much is clear when you see the difference between how Emilia behaves around Subaru, and how Rem behaves around him in comparison.
And how Subaru behaves around them individually.