Need a cat

Guys I need a cat in my life!! I used to have one as a kid and he was my best friend. Now as an adult I have a dog, Rambo. He's my bf's dog and been together longer than my bf and I have been together so I had no choice in the pet matter. I asked my bf a long time ago if we could get a cat and he said no because Rambo will kill the cat and He'd have to dispose of the kitty for me because I'd be heartbroken. He says its not fair for the cat because it'll die on scene and not fair for me. Which I understand. Rambo is like 4-5 years old and I read they live up to 10-18 years. My bf hates cats but says we can get one once Rambo dies as long as we can get another pitbull puppy. I agreed. But guys, I honestly dont think I can wait till Rambo dies... I want a cat TODAY!!!! Lol

Side note:Im obviously going to wait but it sucks