I'm confused as to how this TSS fits in with the others. The rest all seemed to be the result of wishes by the girls, but this time it seems like the supernatural side initiated things in order to "correct" Chika so that she will accept the harem without going insane. I guess maybe Chika could have wished to protect Chinami (she does think about it on the way home from the maid cafe), but the TSS only has a fake Chinami and Chika doesn't actually protect her.
One additional thing I would add to how different Chika's TSS is that this 5th one lacks an exiting. What TSS is about and whether the girls "successfully attended theirs" are more than a tad dubious, but at least Noriko, Futaba, Sana, and Makoto all either got removed or kicked out of their indescribable nightmares by the end of their respective events. This seemingly didn't happen to poor Chika; she didn't come back to reality with a face full of shock and fear by the end. No...she was still in it wasn't she
Btw I LOVE your fake Chinami take a lot more than what I could come up. What is more powerful than not being able to recognize the person you sacrificed for after the willingly subjecting yourself to immeasurable suffering? That you did all of this for
nothing because you were deceived from the beginning. Chinami has always been safe throughout this TSS; Chika sacrificed herself and took all the monster dicks for the sake of a mannequin wearing her little sister's clothing because whatever power behind TSS tricked her into believing that she was protecting Chinami, when the cruelty is that there is just one Chika and one mannequin. Your sacrifice means everything to this whatever power but means absolutely nothing to everyone else, including you and your sister.