Just to clarify "puppet on heat". In this case it's alluding to a "puppet on strings" but the singer feels a more primeval connection to the "puppet master" (or mistress!) than mere strings. There's a more "needy" element to it. So, just as dogs can be on heat, that's how the "puppet" sees it.
Hope that clarifies it.
As for therhyming, yes I was rhyming "whim" and "exists". The third one, by the way, I called an alternative chorus as it starts out like the other choruses in the first two lines but then transitions into a longer third line, which slows down to an end. In that one lines 3 and 5, and 4 and 6 are the rhymes.