I am not saying the being something immediately mean its swinging. It opens up the possibility for swinging or to write swinging. Because the idea of swinging need to began from somewhere. The root. It can easily turn into cheating, cuckold, corruption, gang bang or anything else sexual for that matter. Only thing I disagree with you is that swinging simply means sharing your partner with others while other share theirs with yours regardless of anything.If MC is a harem? What that is meaning? Harem means a lot of partners for one person, partners have relationships with one person...
If main girl is slut it doesn't mean that her partner agree with that. It's illogical (why people divorce after cheating in that logic???).
Any intoxication affects on our behaviour, but this condition doesn't mean that intoxicated person consensually agrees with everything. If somebody will fuck your partner on party, this doesn't guarantee that you or your partner are consent to swing - it's more similar to cheating or rape.
As for money, MC isn't really happy about the situation. Yes, MCs are manipulated to this ending (because female one is kinda slutty, when male one is strongly bullied before by antagonists), but it's not swinging - it's a kind of sexual abuse (implied consent). MCs don't come to idea of sharing partners by themselves, they were manipulated by different methods to achieve this point of life.
Step by step personality of male MC is being degradated. As for female MC, it's more difficult to conclude - her consent depends on route ( and it's getting worse for male MC because female loves sex while her partner is not gifted at all...).
Let start with Harem. Lets say MC is... or wants to be a harem. He would want to bang lot of girls and have them around main girl. This does not mean that main girl is not okay with this. MC propose a lets swing idea. I get to bang girls I bring around, you get to bang guys you bring around. Let all be friends vice versa. Terrible writing? Maybe? Unrealistic? Most likely. But hot AF for NTR games? 100%. Boring? Very likely.
If main girl is a slut in a relationship, she is not gonna disclose this with MC. At least no real girl in a dating scene would disclose that they are a slut to their partner fiction or not. Main girl would wanna try other dicks. I mean she is a slut after all. Thus the potential is limitless to write. The idea of swinging would be propose by the slut. Terrible writing? Maybe? Unrealistic? Most likely. But hot AF for NTR games? 100%. Boring? Very likely.
Drug is usually the gate way to all kind of sexual degenerate stuff. Like you say it doesn't mean that the consent real. But it can also means that the consent is indeed real. It goes both was. But the good thing is the writer get to choose which way it goes. Mc and main girl gets drunk and high, discover what they missing in their life, desire, lust etc. Terrible writing? Maybe? Unrealistic? Most likely. But hot AF for NTR games? 100%. Boring? Very likely.
Money is just simply pay to bang MC girl, and MC to bang his girl. Simple and straight to the point. Probably happens in real life more than we care to believe. and the most realistic. 100% boring writing.
But as for this game, this update route is not really cuckold. The MC is not really getting cucked. I mean there is elements here and there but it over shadow hints of swinging (massage scene), prostitutions (only fan and club), incest, hopefully I am wrong (Jason mother and sister), and gang bang (gang members), and a bunch random other stuff. MC did finally get cucked at the end but there was no build up and it didn't feel like it because main girl didn't enjoy it.
Anyways agree to disagree. Love this series, but I think I need to start my own series.