It seems the scope of the NTR are just one main girl and secondary ones, probably the intention is making the MC have a "dark phase", then snapping out of it and the FMC the one that doesn't fall in the end, like a sort of breaking the cuck circle. And the manga itself is not as bad as I thought it would be, is not that edgy compared to other similar mangas, at least for now. I thought it would be much worse, it's relatively tame.