"shished" "mished" ?
As far as I know these aren't English words.
That's a Russian selection rhyme. The original doesn't make too much sense either.
That's an attemp to translate a Russian absurd phrase. It uses some words which doesn't actually exist in Russian, and doesn't mean much sense. I have never heard it before, but perhaps it's a kind of children's folklore or something.
Should we delete both the Russian and the English?
eng
He shished, mished, farted, got out.
rus
Шишел, мышел, пёрнул, вышел.
I think that at least the English should be deleted. I would delete the Russian, too.