I'm thinking of locking up my cat in my bathroom.
Why would you want to lock your cat up in the bathroom?
I think locking my cat in the bathroom would be much more cruel than just simply murdering it.
Locking up an animal in an enclosed space is cruel behavior. You should love and take care of your pets. If you want to inflict cruel punishments on your cat, you should give your cat away to someone else who can better take care of it and give it a loving home.
Okay, I'll try to see if anyone else wants it.
People get pets before knowing how much responsibility is required. Next time before getting a pet, research how much time, money and effort they will need.