It's been a few months since I played through the game, but there are no direct commands given during the hypnosis at all. The hypnosis scenes are suggestions rather than commands: "Your boobs will grow bigger", "You will be more accepting of same sex relationships", or "You are in love with me".
The effects are not instant, there is no forced-sex hypnosis ("You will fuck me"), and all hypnosis scenes generally last only for 3-4 lines max before the girls (or MC) snap out of it.
Honestly, this story could have the plot device be anything and little would change, though one recurring plot point is the hypnosis effects are unknown to the person being hypnotized.