This stance is usually paired with other signs like an arched back, dilated pupils, or growling. Discomfort or unease is another possibility. Cats might flatten their ears in new environments or ...

Just such a project is [Radomir Dopieralski’s] set of wearable mechatronic cat ears. A cosplay accessory that moves as you do. Very kawaii, but fun. You may have seen the commercially available ...