When xandra fucks the merc for intels, thats still sharing, maybe even Netorare, because the MC seemed like unaware that she was fucking him plus the her saying that he is just a cuck etc, if she was just acting and he was aware of it then its sharing, I stopped playing there because I'm not into cuck/sharing stuff, but still good Luck with the game.
Thanks for pointing this out, you saved me from downloading it.
Also it sounds to be like the scene being discribed here is NTR, not swinging/sharing.
Swinging = swapping partners
Sharing = Sharing a partner with a 3rd person
NTR = a whole bag of worms, but aspects like secrecy, name calling and denigration of the MC tend to fall under this heading.
In the example given above, the MC is both unaware and denigrated which would make it Netorare (classic ntr). If the MC was aware and still unwilling or powerless to stop the situation it would be Netorase (also called ntr on F95).
"cheating" as a tag is typically reserved for the MC and can sometimes encompass Netori (which is the MC stealing a partner from someone else).
To be clear here, I don't care what content you put in your game. It's your game so do whatever you want.
It should be tagged appropriately though, for transparency to players.
Best of Luck.