What the F is wrong with that mother? Probably some shitty experiment or mindgame she wants to do.
Agreed with with the shitty experiment or mindgame angle. But, I don't think that is the mother. Probably a close relative of the mother, thus sharing the same looks as the quadruplets.
Don't know why I would think that woman is not their mother though. Maybe because the reveal is wa~~ay too early? Chapter 8~10 and they already have a first contact as well as conflict with their mysterious mother? Either the author suspect this series will be axed in a few chapters and trying to wrap up A.S.A.P, or they are just incompetent at writing for long term plot.
Come on, there are four characters to slowly build a seperate story arc/back story arc to span multiple chapters, and the mom was revealed at chapter 8 with the backstory of the youngest sib?
I am leaning towards the opinion that this series is getting axed.