Kei has a little sister, so why would Kei need to be the one to give their mom grandchildren? Unless...
Even if Kei's sister is a boy, it shouldn't matter. Boys can impregnate girls, y'know.
Or worse. "Mom" is impatient and wants grandkids ASAP, regardless of the means, with Kei's younger sister still being too young biologically. What's worse is that Kei's younger sibling completely agrees with "mom's" methods!
It's still worse than that. Kei's mother wants Kei to be a Gold Digger. She wants Kei married to a rich man right away. Grandkids are just a fringe benefit. Kei's younger sibling can't get married.
