So there's a few things I would definitely change;
- The text in the intro shouldn't advance by itself, that's a big no-no.
- Don't disable rollback and skipping. Just don't.
- It needs some work about how you address the family; he calls his mum by her name and his sister 'sister'? That should be the other way around, right? One thing I would definitely suggest is checking what is input for the relation and picking 'sis', 'sister', or her name as is appropriate, none of these will fit in every context. Also I'd make it clearer that 'renaming' them changes their relations.
- Unless there is voice, disable the voice channel in the preferences. Also setting default volume to 50% for the other channels is a good idea.
With that out of the way, I absolutely love the artwork and character designs, the girls are both gorgeous. I really like the use of hypnosis rather than drugs as well, I like drug fetish but 'drug and mind control your family' is overdone.
Regarding what I'd do to them, I'd definitely play with their orgasms a bit. Make Mary think of him every time she cums; other than that I'd let her come to him at her own pace for a bit. And make Anna masturbate more than normal, but be unable to cum at all; after letting her stew like that for a while reveal to her that while she can't make herself cum he can, and have him finger her to an extremely intense orgasm. She can bitch and moan all she likes, all it will get her is him making her wait longer for her next orgasm.
