Not really the type of game I would play, but I'm out of town and I'm bored...
This was actually surprisingly good and enjoyable.
The relationship between the fiancée and and MC were actually pretty good. Being unable to satisfy his GF sexually and knowing it, must be a truly awful feeling.
Pushing your very pretty GF to do stuff like this is not something that I would ever truly understand. My own insecurity (Playing as an average looking MC), would be too scared that my pretty soon to be wife would leave me for someone else.
The fact that she still only loves her man (And get's jealous) and still have plenty of sex with him is actually kind of sweet in it's own way.
The fact that there is:-
1) Full trust between them
2) She loves only him (despite him being very average looking)
3) Full honesty and disclosure
Actually makes for a very mature relationship and actually one of the better ones for games on this sites. (In most other games, the MC is a complete whore that cheats on every girl in the game with every other girl in the game)
Cuckolding and swinging is not really my kinks, but I somehow enjoyed the relationship dynamic in this game so far. Everything is consensual and the GF really considers the MC's feelings and makes sure that she does not hurt him.
Who knows where the game ultimately goes, maybe I will end up hating it, but so far so good. Good job dev!