So. What's the NTR? Netori? You can steal someone from another person's relationship? Is that all?
Reading the thread tells you it's more than that, but I can't really answer because I haven't got any true NTR content. I had Ginny fuck feminised Harry with a strap-on but she was under Voldemort's control, and the MC doesn't witness it.
I'm also replying to bump your question, and add to it. I did read through the thread, but still can't figure out if NTR is mostly "punitive" in this game, meaning it only happens if you "fail" in some way (like not reaching lover status with a LI). Kinda takes the edge of it, since it's pretty easy to max relationship with multiple characters if you're determined to (at any point in the game, you can always have two conversations with different NPCs and use the back button to ensure you get +3 points if possible. If you avoid talking with NPCs when they're the only ones in the room, you only advance half a period. You can have 2 individual convos and then go to the room where you have the greatest number of NPCs and, depending on your looks, hygiene, etc, you can get +2 with most/all of them. If it's the same room you had your individual convos in, unless it's a classroom in the afternoon (which triggers a lecture if you exhaust the time between periods) talking to all will also score with the NPCs you already talked to, even if they're no longer visible or selectable, they're still "there". So you can earn up to a total of +5 with an NPC this way... Powergaming definitely lets you be lovers with most LIs before Christmas party.
So, my question is: if you're not going for a harem and do NOT want to be the only cock that fucks in the game, is it true that if you have all of your LIs as lovers by christmas party, no NTR will ever happen there, regardless of who you invite? Does NTR work in the same way for the rest of the game, too? And, finally, if you indeed don't see any NTR, do you get alternative content for those LIs that you didn't invite (like threesomes and "moresomes")?
