I'd be getting scared when a cat reaches the 20kg threshold. I'm about 90kg, so thats a 4.5x ratio :)

Cats are the perfect killing machines (apart from maybe sharks) :)

There's a bobcat that lives around here. He's on my porch now and then, and I also see its tracks in the snow.

It doesn't look like it wants to be petted. I stay clear.

Many people don't know that Craigslist has a "best of" which includes this (relevant) post that makes me laugh every time I read it:

https://www.craigslist.org/about/best/ric/6881185958.html

Yep, a bobcat. But much smaller than the one around here.

my cat at its peak weight is about 8kg, and that's the size that i'd get a bit nervous around if i didn't know it's a tame housecat that runs away at sight of a mouse...

See also "why you should never put a chimp and a little person in the same room" by Penn Gillette

>"I'd be getting scared when a cat reaches the 20kg threshold" - most likely even 10kg cat will shred you before you could blink. They're insanely fast and surprisingly strong for size. Furry explosives they are