Wasn't unavoidable when I last played the game but if you didn't play the cuck, you couldn't share your fiancée. You'd have to play dumb and allow for situations where other guys take advantage of her behind your back. Usually the ugly old bastard types. There are other characters that you can "share" but they're not your gf, and if you're dating them to begin with, you're going behind your fiancée's back, and it has (or had) no consequences. I'd expect this game to be pure porn and cater best to those who play to watch scenes of hot models doing dirty deeds, not caring too much about the the whos, whys, whens, wheres etc...
You do have to be a kind of slave master to the FMC to begin the sharing route, but then it turns romantic. Whether or not you like it, may depend on if you read it as your own character's progression, at first being very selfish and matter-of-factly pimping Emily out for an easy way to pay your rent, but that may be the only case where AF approaches Inanna's Revenge theme of the girl not pushing against a "suggestion" to fuck someone else, while being in love with the MC. At a later point, in AF the MC can fall in love with her. From that point onward, it plays just like any other sharing game where you can (or not) accept that your gf continues to do escort jobs. If you share her (in essence, remaining her pimp) you both enjoy it. There are scenes where you can take part in the action, others where you don't but stay in the room (or in the next room), going to those where you 're not there with her and get sent pictures or videos. Despite what it seems, there's zero cuckold vibe in this route. Seems to bother some commenters that Emily starts to enjoy it all a bit "too much" towards the end, but it never reflects on the relationship with the MC. And Emily is a great cuckquean, too. So, in essence, AlwaysFan is nothing like Inanna's Revenge, imho. The sharing in IR is episodic and inconsequential, so you can choose it or not, each time. In AF it's pretty omnipresent if you choose that path.