Ok, First I have to say this game is awesome, one of the best hentai games I've ever played.
But, I'm almost certain its also impossible. I can't beat the lizard boss no matter what I do.
The difficulty level is way too high, and I'm playing on warden mode (Normal).
It feels like the income is not enought and you keep piling up negative passives over and over...
The first time I lost the campaing Karryn was still a virgin, so I was really trying my best to beat this and not just losing on purpose to get fucked...
And then the second playthrough starts, you keep all your levels and negative passives, but loses all investment you made purchasing upgrades.
I lost the second campaing on the lizard men again. I could start a third one, but I feel like it would be impossible now with over 150 passives basicaly making her a cum dump.