>>8523051
>Anyway i would like to know why you think they fell quickly
The most obvious answer it's cause it's a hentai game and just a power fantasy.
they might be into their sons because they look like their former lovers, Ryouko talks about it when kissing her son.
there might be a lot of factors, but like all milfs in orcsoft games they're just slutty enough to be down for it.