Disclaimer.
I have only played each of Lisa's path 1 time each but for the "You got to fight for him" which I have played now 6 times through to make sure I got ever thing.
My statements are base on my play going down the "You got to fight for him" path.
A traumatized rape victim that is abused by a guy that is cheating on her that manipulates her in a way that she is ok with the fact of their son or daughter are in room when they have sex for educational purposes, and don't care he is actively trying to seduce the older sister even when you present to her a photo of him masturbating watching her.
So now in V0.6 your options are to abuse your mother or to convert her in a PornStar.
But she has total authority over Max and Max knows it. I never use what can be gotten from Erik I always tell him I will think about it to keep him at bay for as long as possible. Max is between a rock and a very hard place and is trying to fight for his family the only way he knows how. (You need to listen to aunts story about Anna, before the kidnapping she was just as head strong as Kira is but now is just a shell of her old self.)
That is a professional whore, but probably the only one that cares for you.
No to this 100%, all of them care for Max. Mother does but she is being controlled by Erik. Big sister loves Max as big sisters do by being snarky and putting him down but deep down inside she cares for him.
Now little sister took me a long time to figure out, she is secretly in love with Max and if you play through the "You need to fight for him" path and if the english translation from russian would have brought the passion over you can see it.
There is still a lot of hints to this in the english game and if you look for them you will see them.
Big Sister: An interested bitch that hates you and only cares for the one that give her the best gifts and money no matter who he is. And the only way you can get something from her is if you pay weed to her pimp or make her drunk.
This is only her outward persona and if you watch each pic you can pick up on her secret love for all her family. Typical big sister attitude is how she is portrayed. A lot of the passion is lost in translation but there are a lot of hints to this. The very first time you get to spank Alice when you catch her smoking and you chose the right response she thinks its a complement and if she hated Max this would not happen.
Little Sister: You can convince her to do things she don't want to do with you and later use the love and respect she have for aunt to force her keep doing thins she don't want to do with you or let an untruthful guy to drug her so you can have his GF.
Now little sister took me a long time to figure out, she is secretly in love with Max and if you play through the "You need to fight for him" path and if the english translation from russian would have brought the passion over you can see it.
There is still a lot of hints to this in the english game and if you look for them you will see them.
One of the first major tell tell is when aunt came in the first time for training, the next day she tells Max that Lisa got wet very fast and this is not normal for one who does not want it. The first major tell for this is when they both got off while Lisa was watching porn on her phone, she open up to Max at that time and showed her true feelings for him.
Go back to the opening story, what teenage girl who is offered her own bedroom turns it down to sleep in the same room her brother is in, this is the first hint from Lisa.
Once again I love the "You need to fight for him" path.
Max is limited in what he can do to keep Erik's authority down so he will not be sent to camp and must pay 300 a week to save his ass until he can take care of Erik and while doing this he has fallen in love with his whole family.
For big sister he has to pay her and give her massages to drive down Erik's authority.
Little sister he has to help her with homework and do the dishes.
For mom he has to walk in on her and give her a complement and watch a movie with her and later give her money to drive down Eirk's authority.
This is how I see what is going on in the "You got to fight for him" path.