Man this dev needs an editor so bad. Hell I would do it for them. "We also added a new spelling check" I kind of doubt there's a "we," because all of these mistakes are emblematic of one person who typed fast and hasn't yet read over their work. It definitely doesn't read like something that has had two+ pairs of eyes on it. Which is disappointing, because I really like this wacky story, and I want it to be less full of easy to fix errors.
Examples of the mistakes from a single scene (the baptism/initiation):
"To become a devoted sister tot eh Master" - lots of scrambled errors like this, presumably from fast typing and not reading it back
"Master will stand roughly where Master is stood now" - lots of awkward phrasing like this
"re emerging as your Masters cum slut" - no dashes or possessive apostrophes, this is nitpicky and isn't that big a deal
But the larger mistakes that really take the reader out of the story:
Characters are constantly misplaced, either in dialogue or actual models. It would say Sister Karen when Irina was talking, Sister Emma and Sister Karen when Daisy was talking, and Sister Jasmin's model would randomly take Brittany's place during the "baptism."
Also this is more of a personal preference thing, but for an erotic VN, it's weird that scenes like that have him repeatedly simply place his dick and finish, a decidedly unsexy route, rather than blowjobs, sex, or something similar. I think if you're making a sexy story, and the story is getting in the way of the sexy, then what's the point? The author is certainly aware of this, the MC notes "I feel like a conveyor belt worker. Nun, cock in, cum, next nun, insert, cum, next nun..." but I just can't figure out what purpose it serves besides, at best, setting up some future story beat.