I'm in a similar situation. I finished uni and had no choice but to move back home because of finances. Then I got Mig (rabbit), he was a graduation present from my mum - she gave me the money and I did everything. Then a good few months later I pursuaded her to let me get my dream dog (it took 22 years of persuasion on this, as she wasn't wanting me to get a dog). It did help that I was working in a boarding kennel and showed a ton of responsibility. I got my dream farm bred Border Collie, trained her up, fed up, walked her. My family do NOTHING for the animals except enjoy them around the house, that was the agreement. They are my responsibilty, I treat it as if I was living on my own with them. My mum does take over when I'm away which is rare. Then I switched to volunteering in an animal shelter. Not long after Memphis orphaned litter arrived and I fell in love. Well it took A LOT of persuasion but my mum could see how much he meant to me and she let me adopt him.
I have no chance of moving yet because it's too expensive, when I do move they are coming with me. They are my little family, they are part of me and I wouldn't be without them. My mum loves all 3 deerly but there are days when they annoy her and she realises they won't be here forever.
The hardest part is taking responsibility when they destroy things that dont belong to you, Mig was 6 weeks, Molly 8 weeks and Memphis 7 weeks when they came here - Mig has eaten the bathroom wallpaper, a phone cable, several other cables. He went through a stage of weeing on the furniture. Molly ate the kitchen wallpaper, the cord of a hand held hoover, and has scratched the paint off of doors and broken one chair, and the garden no longer looks like it did. Memphis has eaten through my ipod headphones, the end of my shoe lace and more importantly smashed something of my mums the other day and had an accident on my mums newly ironed pile of clothes. If these all happened in my own place it wouldn't matter, I do take responsibility and apologise A LOT. I'm so glad Memphis doesn't scratch furniture. These are things you have to take into account, how much your parents mind your cat(s) possibly ruining things.
I'm a really new cat owner and still learning everything. Mine is being raised an indoor cat, and is booked in for his neuter in February when he will be 6 months old. As for sex I prefer Males :D