I believe Hili is talking here about her bête noire Fitness, as Cyrus the d*g and Fitness encountered each other last week without rancor. Andrzej dreams of getting a picture of the black Fitness together amiably with the black Cyrus.
Hili, of course, cannot abide Fitness, who lives upstairs with the lodger.
Cyrus: See? There would be room for another cat.Hili: What? Has he tried to muscle in already?
In Polish:
Cyrus: Widzisz, tu by się jeszcze jeden kot zmieścił.
Hili: A co, już próbował się tu wepchną

It’s funny how animals decide if they like each other or not. My dog will either happily play with another dog or jump on it and hold it down (which escalates to growling and biting). Dogs tend to size each other up in a matter of seconds.
I also like that they aren’t afraid to tell the other guy they don’t like him. I imagine animals just outright saying, “I don’t like you; go away” if they could speak English.
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