Yep, I also spent quite a while poking around their sections hoping something could work. Seems like since virginity loss is required for monster combat rape to occur, they simply took out the NPC events that would've allowed that.
Oddly though, using a Unity asset extractor reveals a lot of animations that seem to be unobtainable in the trial but are still in the game files for some reason. There's a good chunk of extra scenes for the black hair girl and a few for the other two main ones. Not sure why they would leave in the data for so many animations that don't appear in the demo.