Snoopy the Musical query

I love this show, but there's one lyric I've never been able to work out - I spent years trying to get even the words before the net helped:

The World According To Snoopy
Is big enough to go around
Four billion people plus, that’s the “pop” of
Still we got room for sitting on top of

But what's the meaning of those two last lines together? The last line must refer to the kennel, but 'pop'? Obviously, this is of great import. I thank you.

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Thank you. What an awful lyric - not representative of the rest of the show, thankfully.

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Sandy can throw in the tow-el.

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