Cuatro gatos
 

Hi,

I stumbled upon cuatro gatos mal contados. Is it there's pretty much nothing/nobody around?

Besides, I found an unexpected wealth of cuatro gatos idioms on Context Reverso.

Is there any system about cuatro gatos in Spanish?

I don't know about system or origin, but it's a simple set phrase meaning "very few people". The number is big enough to be a plural and small enough to be counted with the fingers of one hand.

- En la conferencia había apenas cuatro gatos.
There were very few people at the conference.
- Yo nunca cocino cosas complicadas. Para cuatro gatos que somos en la casa, ni vale la pena.
In this case, probably four people is the exact number of people living in my place, but I still think four is not enough to bother cooking complicated dishes.
- A la fiesta no llegaron ni cuatro gatos.
There were far fewer people than were expected for the party.

Thanks! Does mal contados, in my case, have additional meaning? Or zero, for instance :D ?

En la conferencia había apenas cuatro gatos.

Can I say

En la conferencia había cuatro gatos mal contados.

?

I guess "mal contados" is just a way to add an emphasis on the small number and a touch of contempt.
Yes, you can say that. :)