So, I tried to do a calculation of how big the population of Lungfishopolis is. In reality it's not really possible to accurately calculate the number of apartments each type of building has, and that's besides the fact that most houses really confused me (like, how can a house not even contain basic doors?), so I advise taking my calculation with a grain of salt and probably do your own calculation. Despite being sort of a metropolis, it's actually quite small, though a lot bigger than it may look from the perspective of the player. I counted all the buildings that looked like apartment blocks, and high-rise buildings:
All the small types of homes, ranging from half of Razputin's height to just a little taller than him, combined would have around 7 917 lungfish. While those buildings were fairly easy, the skyscrapers were a nightmare. Such a huge nightmare, in fact, that I went lazy and just estimated how many lungfish could live inside of these, which lead to possibly 10 225 lungfish living in these tall boys. Which would mean that the population is 18 142 Lungfishopolis citizens in total.
This might seem like an over-exaggeration, as, again, the city looks fairly too small to contain such a large number of people (lungfish in this case), but considering how many navy soldiers there are, with all their tanks, ships and airplanes, I'd say that's a pretty reasonable number.
I don't know why I did that, I was just wondering about the sheer size of Lungfishopolis and, again, you can do your own calculation and correct me or confirm this number if you want. I could go on more detail how I did my calculations, but honestly my paper looks way too messy to be legible by anyone who's not me. Have a nice day.