Runa has 16 kids and is just going to high school like normal. Are there 16 high school aged single moms out there? Since Runa is going to school, I doubt she has time to work and pay for child support. Are her parents rich and taking care of the kids financial needs? Does she ever visit her kids and attempt to be a father to them? I don't get the impression that she gives a single fuck about her kids, beyond feeling a sense of conquest / accomplishment that she got that many pregnant.
"From now on, let's have lots of sex until you get pregnant with our baby, okay?" Runa gives the impression that as soon as she gets a girl pregnant, she dumps them or just disappears. How is she getting away with this? Hentai logic. The author doesn't think about it, so I guess we shouldn't either.
Runa's penis is weirdly drawn. In some shots, you can see a foreskin. But most of the time when it's flaccid under her skirt, it looks like she has no foreskin.