It's fantasy though, and all-female species like monster girls are commonly said to reproduce by human men.
I forgot where it's said exactly but I seem to recall that the MG's have a choice when there's semen inside them. They can choose to be impregnated by it or consume it.
Pretty sure that's from Monster Girl Quest. Dunno if Threshold ever stated outright that pregnancy is/isn't a thing. I would more argue that since monster girls in this game basically outlive most Human's (assuming they don't try to split the atom within the vicinity of
EVERYTHING), there might have been reproductive stuff going on before, but now it's like "yeah, multiple generations and shit, but also we're confined to an island of sex." Otherwise, I owe a
FUCKTON alimony to a lot of harpie chicks.
I don't understand the anger towards Beris being a brat in the Labyrinth. It's pretty on point for the character and depending on your responses, she slides out of character and let's the sub leak out. MC is simply being a nice guy by not actively trying to get her to sub out in front of her sisters. She's over compensating for the fact that one "good girl" from MC would have her on her knees for the world to see.....Seriously, even her little temptations in the Lab are full of repressed sub depending on what you choose. I don't know maybe I just like the variety in personalities....
The issue isn't her being a brat. It's that she's a garbage person due to her excessive tsundere nature, combined with that headache of a fight if you ever encounter her. You either invest in the "fuck this shit I'm out" perk or over-level, because otherwise you're gonna have a bad time. Also, optional side content shouldn't be counted. Every competent writer
knows you only write spin-offs/side content to further expand the existing content and exploit whales. You
don't use that stuff to explain the terrible parts of your story. If your story/characters need an entire novel of side content to be good, then you've already failed in making them good.