I don't think you read it properly.
She isn't setting up a harem in her house, she's set it up so it looks like her brother has lovers and she's there to keep him out of trouble.
What goes on behind closed doors is one thing but the story they present to everyone else is the MC has one of the 3 as a lover and she's there to keep an eye on him and get over an "emotional" breakup with her ex.
The stories are separate. Jessica doesn't have anything to do with Andres. They are testing various people out to act as the beard in their relationship.
Andrea is a submissive while Jessica is a dom. The 2 stories don't have anything to do with each other. You can't end the game with all of them, you can only pick Andrea, Jess or Maria.
All the girls stories are kept apart from each other, once you go on the second date the other 2 are dropped.
the stories are separate but MC is the same character, which carries on for a long time with all 3 women, the event which then defines with which of the 3 eventually will have the ending gets very forward in the game.
for me that he makes Andrea sleep at the foot of the bed like a dog, and that he accepts to be "mistreated" by Jessica the next day does not seem credible.
and there are many steps with them that are in fact mandatory, and you can never say "no thanks", you can only do it very far in the story.
what MC has in the house is a harem, how else can we define it? of course it is not public. and having two other women that MC can be seen around doesn't seem like the best way to be low profile and go unnoticed. the same goes for the swingers club, these are all risks that do not go together with Dana's fears of getting caught. how to involve a girl you don't even know to pay homage to MC ...
how credible is the excuse they use with their father? How long can a sister put tents in the house of her brother and his partner because emotionally shocked? a week? two?
they are all pretexts to make certain situations happen, but a real, common story does not exist.
