Up to raw 36. I'll just give a general overview of what Zero mentioned above and clarify some pointsif anyone cares.
Spoilers
Obviously spoils story. I don't speak jp so Google translated hella pages.
Zero is right, the main girls do anything in the dreams the mc create. The dreams don't affect anything in reality the characters literally fall asleep and dream of whatever he makes them.
The white hair girl with side swipe and brown hair girl with white center hair are basically free use irl though. They sleep with anything for pleasure like the mc, golems, and other women, maybe more but couldn't tell. These two aren't part of the main harem anyway however more side characters.
Pink hair girl,pink glasses hair girl, beast women/demon women, short yellow hair and long yellow hair(fmc) girls all are exclusive to the mc and have only slept with him. Fmc does have twoish~ close calls with other guys and ntr bait. Fmc doesn't loose her actual first till like chapter 20 or in the 30s with mc most of the time it's only dream world.
In fact I can barley tell if it's all only been dreamworld as even if he says he's going to take her first, he decides not to and uses a ikemen type character in the dream world to bang her himself. It's unclear if he's actually done it especially with MTL but surely one of the times must have been real i think...
They do definitely remember all the dreams(?) but they don't see them as dreams till their told later.
Idk what zero means by sex cult and all that. Their was like an auction where the white hair and other side girl are sleeping with guys and she sees a few other random npc comrades sleeping with guys in tents. She almost gets forced to join by a guy but mc sleeps all them so nothing happens.
The rest of what zero said idk either ngl its just a bunch of random repetitive stuff after ch 20. Imo there is no ntr unless you want to stretch the definition really weakly, I was pretty lazy reading so maybe some parts iffy but yea.
Very generic lewd isekai with decent art occasionally, terrible story, ok characters, bad humor and no villains basically. After ch 20 it just repeats slice of life sleeping with his girls. Pretty mid.