The content of Binhai City in the first volume is about to end. After a few small plots, we will fight the boss and sort out the subsequent plots.
The sisters' brief exit was a plot that had been conceived long ago and was related to the subsequent content, and it was not something that came up on a whim. However, the original idea for the separation was to be more pure love like it is now, rather than the first version. To be honest, I don't know how something that had been in the outline for a long time turned out like that when it was written down. It may be related to staying up late these days.
The author then went to bed.