Dude what the fuck he asked a simple question is NTR avoidable or not is not that hard
With the immediate family group is where the CM can manage the situation a bit more, since they are not involved in TESS, but the mother was there for a while, so here, depending on the CM's decision, it can be a bit “less NTR, more Harem”, it can also be more ambiguous to corrupt or to share, or to lose control.
The other characters, most of them, if they are corrupted so the options start from “take them out of TESS or to the church, or be part of ‘Harem’; or as the previous ones, but if they have already had and have relations with the cult.