Your cat sounds perfectly normal. My boy cat was the laziest bum ever, he'd be happy sitting in his spot under the table or on my lap getting a belly rub and ate like a horse. My girl cat would be happy if you gave her a piece of paper to play with or simply chasing you around the house trying to bite your ankles. And like kitty boo's cat, every so often, you'd hear her thundering around upstairs going crazy for 5 minutes then go back to sleep. I wouldn't bother buying cat toys when there are so many things around the house that make great toys, like a bit of string.
Posted by knees
Our old cat, Blackie did nothing. that's it. he didn't play, he wasn't affectionate, he didn't purr, he didn't like people except me, took on a german shepard and won lol. He was happy, he got fed, he got a makeshift greenhouse to sleep in outside. he lived until he was about 14!!!
My kitten Charlie is 5 months old and when he's not sleeping he runs laps round the room, plays with cotton buds, on the attack constantly, jumping, running, climbing.
Cats seems to vary personality wise as my two experiences display so i wouldn't worry about it
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