Did you figure it out? Is it post game?
Viewing post in PURE NIGHT : Futanari Infection RPG comments
I figured it out saddly, it's before you get infected, at the begining of the game instead of fighting that girl with a pistol you go to the right, the sad part is that there isn't more interactions or a game over, "black" giantess just holds you in her anus and clenches to heal herself, not causing damage