MUM-161 has such a relationship for one of the couples. And there is even an English-subbed version available at https://javengsub.com/watch/MUM-161-Hairless-Pussies-Next-Generation-Future-Wifes/
I always appreciate a new subbed Jav. Thanks, javsubbed. With the openload SD version of the movie I had to delay the subtitle track about 20 seconds to get it synced right, but otherwise it works great. Many thanks.