BlueStorm

I came across a post abou saying subaru relys on rem different from beatrice and otto. And the top comment is saying subaru doesn't trust rem because he believes she will die... subarus unique relationship with rem is such a basic aspect its so scary, how little people know.

Second key context: Rem becomes tasked with watching over Subaru while he heals. We see here that normally, Rem has many restrictions in place when she is with Subaru. And very important, she's worried that if she had to watch over him herself, those restrictions would fail.

There’s no guessing here, no room for interpretation, and no space to add your own headcanon. The entire point of the night scene is to be a direct contrast to the morning. In otherwords the night shows exactly what happens when Rem is not able to hold herself back.