we dont have the corruption of the pink haired one ?? (seems like the author reuse these characters multiple times but I dont think I saw the succubus one yet)
The main series' setting establishes that the rules of the world conform to the imagination of Akari's father (see /s/633acb57c2/2554996-3) and he designs it in such a way that he creates stupid reasons for the female leads to have copious amounts of sex, like making their magical girl power be dependent on how much sex they have. So basically the "connection" is probably something like "Dad was bored so he went for a full-universe reset so we could get lewded again."
As much as I would have loved to see more of their corrupted forms in the main series, the pink girl's corrupted form looks a lot better in this version.