The title of this movie is "Husbands Teaching Wives How To Suck Cock"
I think its more like the husband is looking for an excuse to suck cocks than teach his wife. (not that there is anything wrong with that). If fact, his wife is more than happy to share her husband. And is happy to share cock sucking with him too.
Looks like two gay guys sucking each other with a very attractive, wholesome looking girl with very small but very nice breasts mostly just looking on and "being there." I love watching straight guys try cocksucking and with just a little imagination, this works. Abrupt ending is a bummer.