So maybe I'm missing something here, but I have zero backstory on exactly what is going on, just right to the girl rem as if we established being with them. Nothing on how we met and have no clue about things that led up to this, only that towards the end we are in heaven and some bald dude is telling us about another chick who is a sito?
There is zero lead in here, and if you want to tell the backstory later thats fine, but your first 3 chapters worth of images probably should have all been about Rem, How you met her and why she is so loyal to you. We really need to build a connection to the characters if you are looking for people to latch on to "best girl" attitudes.
Asada and Rem are cute, the other two seem pretty run of the mill.