Sukeban Gamesさんのイラストまとめ

Her second iteration was made to look more like a Heisei idol, including a more casual look and style
Idols need to be the right amount of "approachable" and "untouchable" in design so Kira★Miki was a surprisingly tricky character to come to terms with

This is also the day where a certain Idol shows up
We've posted before that Kira★Miki underwent a design evolution. This evolution is actually related to looking for the right kind of idol
Her first design was made to evoke Showa idols with the required Feather Boa to go with it

PSD*

Speaking of earlier sprites, Jill looked very different once upon a time. This early design was even labeled as "Jillian" on the filename since she was a simple genderswap

Her final design can be seen on the menu screen of the Ren'Py Prologue however (ft. Fluffy hair Alma)

#DailyVA11HallA Day 8 and it's time for the second day fo the full game!
This is Dorothy's first appearance in the full game and here we see her sprite evolution.
Last one's file name was labeled "do not replace" since the original PDS was misplaced somewhere

It got replaced.

This day is the first appearance of Sei. Even though she got namedropped by the Stella cameo back in the Ren'Py Prologue this was her first appearance... which is interesting considering she was the 4th character ever designed. Predating even Betty and the dogs

Changes include a visible age bump and making her missing arm more obvious, however, you can still see the older (younger) sprite's face when Anna shows Jill her ID
Anna's demo was the first time we wrote the bartender with a more defined character and called her "Jill" too.

Another bit removed from the redux version was a dialog where Deal discusses that Lilim don't blink since that would result in intermittent loss of information. This was a nod to explain why Deal and Dorothy didn't blink... which got removed because now they do.

#DailyVA11HallA day 5 is for the final Prologue day!
In the original Ren'Py version of the game you could find Stella (here in an earlier version) as the very last order of the game, a sort of teaser. This is also why when she first shows up she mentions the place looks familiar.

Prologue was originally made to tide people over while we finished the full product, however, it showed the technical limitations we would run into later, so it served as stopgap while we started over in Game Maker Studio
And here's a comparison of Betty then and now

The Bartender inspiration kept showing through. When Jill came to be as a character she was made to be the opposite of Bartender's Main Character
Where Ryu Sasakura is a mysterious prodigy that studied in France, Jill is a half-French mess of a human being that only LOOKS cool