these are just little ideas for bad ends I had so take these with a truck of salt.
1, if you fail to hypnotise Jane she decides to follow through on always calling Jason girly by hypnotising him into walking around in a dress and heel and becoming the girliest member of the household.
2, Noelle could instead use Jason to help make her less stressed about work, making him her kinda secratery.
3, fail to get Kira and she'd basically use the hypnosis to make Jason a act just like her, green dress and everything.
4, Fail to beat Sarah and we could get a ending where the whole family are puppies and Jason is either a neutered puppy or a female puppy.
5, a kinda mega bad end where instead of becoming confident Jason breaks so they girls decide that they don't need a guy in the family and remake Jason as the new sister Jess.
So yeah, massive truck of salt.