Damn, I really disagree with the authors decision not to include the pixel art defeat ejaculations outside of the gallery. They should've been in the normal exploration mode and then if you lose all your hearts, you see the full defeat animation.
Sorry for the random reply to an old post, but it needs an english translation (which I think it has, last I checked the DLsite page?) and then someone needs to request it in the Game Requests forum. I wouldn't be surprised if someone requested it already and it got declined though, since this kind of looks like a game that wouldn't make it past the R7 check.
Worst that happens if someone requests it is having the request declined though, so... if anyone wants to go and do that, they can.