My mum took saints 2 from me coz im too young! :(?

I bought saints 2 from argos with my mum but now my mum and dad dont want me to have it coz they feel its too gory. I know that some people grow up from these games and get into bad stuff, but i have been brought up with good parents and i have a great attitude and grades at school, but yet they dont want me to have this game. i have far cry 2 but i got that online and she says i still dont know where you got that from. Can someone back me up to help me get my game back from my good folks ?