Really good chapter! I liked how realistic Seira is. I bet there are a ton of guys like her.
I wonder how common polygamy is in that world. It's weird how there are so many women with a boyfriend in the manga.
it's not legal. It's been previously mentioned in-story, but there's currently a governmental petition to legalize it within the nation of Japan, but it's all background lore that's only brought up when it's convenient for whatever's happening in the chapter.
I'm a dumdum, read "polygamy" instead of polyamory.
Hard to say how commonplace it is, but we do get a couple examples, if memory serves.
But likely runs into the same pitfalls it sometimes does IRL wherein if the women aren't friends, then issues of jealousy and hierarchal infighting for "first place" would be a thing.
And since a lot of the men shown come across as a touch hedonistic, or at least self-centered, it's likely that there's an incredibly competitive current running through each grouping wherein it's not so much "one dude loves multiple ladies" and more "dude picks up and dumps ladies at a whim and the ladies all fight to stay out of the Bottom Spot".
(But this part I stand by) - It honestly sometimes feels like the author sorta forgets about the disparity unless it's specifically relevant for the chapter, or we just have a major case of sample bias for the sake of portraying the plight of the heroine currently in focus.
Because her three friends all having (presumably) separate boyfriends feels like a statistical improbability, given what we've been told up to now.
If each of
them are sharing their respective boyfriends with other women, then that would go further to explain things, but again - it's not made clear one way or the other, and I don't know if the author's doing that on purpose to keep things intentionally vague, or if they're just not fully thinking it all through because it doesn't directly relate to the main cast of six.