Cat is the easiest choice, just eat and sleep all day, but they only live about fifteen years, and if you end up in a shelter and no one adopts you, you're screwed.
I'm tempted to choose an apex predator like a wolf, but what am I going to do when I'm too old to hunt or I get injured.
I think a seagull might be a fun choice because I can fly anywhere without being noticed and eat anything.
Tobias is right, bird of prey is probably the best choice.
Wait, parrots live a long time and can almost talk.