Each enemy seems to have its own specific counter that builds up to the main character's overall stats. For example :
The pollen pod, flies, ground tentacle, and parasite utilize the same stat that, once you reach a certain count [ 100 - 150 ], will result in the character having a different set of lewd voices and flavour text; although this is only a second stage set. No third set spotted. The tongue creature, on the other hand, has its own counter and doesn't follow the same stat as the three listed before.
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You can't see these specific counters yet since that feature is an item that appears at the end of the game based on the creator's responses on Ci-En.
Also, you can also encounter the extended climax on the tongue creature utilizing cheat engine. The thing is that the game locks this out of the current demo by capping it below that point; so you'll have to fiddle around with cheat engine to see it. You'll start seeing it when you mess with the counter to go above 200.