Cats' eccentric personalities are usually manifested in the following ways:
Independent and aloof: Cats tend to be self-reliant and do not need excessive human companionship, sometimes exhibiting an attitude of isolation from the world.
Rapid mood swings: A cat's mood may change suddenly, from affectionate to indifferent, or even show aggression.

Picky eater: Cats are very picky about their food and may refuse foods they previously liked in favor of other flavors.
Nocturnal: Cats are active at night and sometimes exhibit strange behaviors in the middle of the night, such as running or meowing.