The premise of a cat that is somehow bipedal, exterminating rats who are also somehow bipedal, along with them all wielding guns... is certainly silly but adds to the charm of this game! Whilst the demo is surprisingly short, the gameplay is solid and quite reminiscent of Doom.
The "9 lives" is a fun little nod to cats having... 9 lives! My only real criticism is the lack of enemy variety beyond rats with different guns! Environments might also be a bit too dark or the rats blend in too well along with being pretty small targets!
In any case, I look forward to the finished game!