If I'm reading everything right, I assume, Mr Dots geared his game into forcing a girl to have an open relationship or breakup. The intent, I assume, was to give the mc a golden ticket. He wanted the mc to get around and not gate people from other paths.
However... it came off in a way that she was an unforgivable cunt, as such he retconned it and made her want fidelity.
Quite ironic I suppose. Narrator was trying to give us a gift: the story was geared in a way where the mc could guiltlessly cheat, but because of how it was handled it was a gift no one wanted, and now cheating in game is illegal.