transformation is in 2 things (mcs cook gets bigger in prologue, and 1 girl can be made futa (your choice ingame).
ntr can be deactivated via controlls and blocks that off completely or avoided while playing standard mode.
corruption isnt necessary for most content (except for anal in some girls and for mother+daughter scenes- there are 2 pairs doing that currently). drugs arent in the game per se. mcs sperm makes girls more horny/corrupted, but can be deactivated by drinking a potion (see walkthrough lucius) or by not cumming in their mouth.
i still advise doing "some" corruption or you wont see anal scenes or scenes with the julia (mayors maiddaughter).
i think all voyeur scenes are on ntr path except for spying mira solo undress in her room.
please be advised while the game still has a lot of content, you exclude about half of the game with your selection of red lines