Great... another dev that has no fucking idea what he's doing.
NTR and harem NEVER work together.
The harem crowd will NEVER play this game.
Good... now another "insight" to help you develop the game... girl on girl should always avoidable aka not happening if the player decides so. And never behind MCs back either, or you have NTR again. Most people aren't as forgiving as they used to be when it comes to lesbian sex in harem games. Best practise is to just stay away from NTR and lez in harem games.
I mean... obviously... this dev has no idea what he is doing... the incest crowd hates sharing almost as much as the harem crowd.
This is a cuck game on all paths because neither people that like incest nor the people that like harem like having another dick in their game.
This game is basically dead on arrival and the dev marked himself as cuck-dev already.
The trust is broken.
So i have to edit the script myself... oh well...
EDIT: I removed all references to MC calling his mother and grandma by their fist name. Even them asking MC to do so.
Now the game is an incest game again.
If anyone wants the edited script.rpy file just DM me...
Kinda sad that the dev won't change it or better yet implemented that in the fist place... oh well...
Not a big fan of MC calling Susan by her name now... that really ruins the kink.
Actually that goes for Cindy too...
The M/S and A/N dynamic is quintessential for this kink and without it it's just two people that haven't seen each other in a long time fucking. The B/S dynamic is different though it doesn't hurt to have a few e. g. "big brother" or "little sister" in it.
Apart from that not bad a game... even though I know where you got your inspiration from.