Sadly, from the npc on npc stuff that's already bad enough to have having to know or see a love interest is sleeping with someone else. So some might call that ntr from a player pov if it upsets them in some way or like the ones who think their Mc should be the only one with all the girls and also those who for sure who would hate their Mc getting sloppy seconds in a way like seeing some girl have sex with some guy before he has to go to a battle and dies, and the girl goes to the Mc for comfort and the two can get together later and the ones who hate it would say no to her not wanting her since she is used goods or whatever at that point or whatever you player are thinking as everyone is different. So if you want ntr in a way the game has it if you want to think that way due to the npc on npc stuff.