Because of this exploit I found, I have no idea how to get through there the intended way lol, every time I've played through the game I just wen through the gap
First thing your missing is the second h-scene you get from the fox boy, if you havnt already talk with him after the fight you should get it, The second missing one is the big blob/tentacle creature in the slug den, it pulls you in and forces a lewd scene. if you did these, and didnt get the h-scenes the gallery is bugged, im gonna patch that as other have had gallery bugs
I've seen 2 issues with the gallery, first is that if you get the h scene but don't save before death, you lose the scene, you have to save after getting it or you lose it.
The other is the tentacle monster to the right of the fire demon we summon, it should be a soldier or something since the animation is not the actual tentacle monster.