Cats have a several of those signs. Slow blinking, still tail, etc. Seems like it's very important to signal when they're relaxed and secure and when they're not; likely because they're full of claws and teeth.
I inherited a male cat, now about 4, with a property. He couldn't follow the previous owner because he mostly lives in the woods and there is none at the new place. He is wonderful and amazing. I send videos and the guy tears up when he gets them. One nick name for him is Garage Lion.
Yesterday I had to invent 'cat sticks.' He likes to sleep curled up in my planters and that kills the sprouts. So all the planters but one -- the designated cat planter -- have random sticks now...
