I wonder why that freaked out the pets...?

Perhaps it's some sort of pun that isn't translating very well.

The only thing that comes into my mind is that Satori said "Shiko-Shiko!"
And since she said without a pause, it sounds like "Shik-oshiko", which is what children often say when they have to pee

Of course, this can have nothing to do with the pun/punchline intended, but it's the only thing that comes into my mind

Pets are not allowed on the sofa~

or maybe just because satori acted up.. cute o_O