Just in case you haven't gotten the hint yet from the previous comments, this 'story' (More like a peek inside the mind of a perverted author with dubious fantasies, let's hope they stay just fantasy!) is attrocious! I wrote my own review on anime-planet and will also put it here:
Just a slight warning, this will contain spoilers, but I don't think it matters really, because you should not read this smut to begin with, unless you have a very specific 'taste'....
Also, trigger warning, I guess, because I am going to use the R word for sexual violence, as this is what this whole damned story is about. Well... Maybe not just that, as it is pretending to be an adventure isekai sort of story with dungeons, but FFS!!
For some reason, I came across this isekai on FB. They DID NOT explain that this was going to involve a LOT of RAPE!! (Or any sex for that matter, it only showed the summoning part and I like isekai, so my bad on that) The first chapter already got me worried, when the whole class was summoned, but they only showed the guys being present and my fears were confirmed in the second chapter. What's worse, MC doesn't even care and proceeds to ALSO RAPE his classmates, because they were wearing slave collars that made them emotionless anyway, and they only just started the schoolyear, so he didn't know any of them either, so "Who cares."
DUDE, WTF?!?!
I am almost afraid to say that I scrolled through the next chapters (28 at time of 'reading'), in hopes of finding any redeeming factors, but they actually double down on making things as horrible as they possibly can, because we then find out that the girls (or at least the ones we are getting a perspective from, on their side of the events) actually ARE aware of what is happening to them, but there is nothing they can do about it!! Surely that won't cause any trauma, right? Though I guess for the guys, having to risk your life in a dungeon isn't easy street either, but... Seriously, WTF is wrong with this world? This manga? The artist that wrote this harem rape fantasy?! The women in this manga are treated as mere incubator objects, even if MC tries to prevent impregnation on his whim... This whole thing just makes me feel disgusted.
How the heck this almost has a 7/10 is beyond me. I'd hope it's just people trolling, but then again, rule34 also exists for a reason and there are plenty of people with a different mindset and prefference, so... I don't know, you do you I guess, but stay away from me!