I wish there were more options when reviewing games online. I see all of them with NTR warnings and I wish they would clarify, Netori or Netorare. I personally enjoy stealing or cheating behind someones back in a VN. As for Netorare, I would prefer Netorase or go full poly instead of being cheated on. problem is when you block all NTR you end up with a bunch of vanilla relationship choices.
NTR is more than just being cucked!
full support
Honestly, more tags in general would be better. The more specific, the easier it is to find what you're looking for.
As a lifelong poly person the concept of NTR never made much sense to me. That, and I don't speak Japanese 
Maybe we could get better clarity by using English terms...
cuck: MC is cucked by NPC, whether or not MC is present
bull: MC cucks NPC
rival: MC has to win the affections of an LI from a rival NPC
voyeur: MC watches other people have sex
3p: Player is shown sex scenes between NPCs without MC present, such as when a love interest remembers past adventures
cheater: MC cheats on a partner without their knowledge or consent
cheated: Partner cheats on MC
sharing: MC consensually shares a partner with a non-partner
shared: Partner consensually shares MC with other partner
triangle: Two or more of MCs' partners have sex with each other (there's probably a better term that could be used here)
Did I miss any?
I'm not sure if cuck and bull should be used as broadly as I have them here, since a lot of people think of cucking as specifically having the non-participant in the room watching, so maybe there's a better English term for when a love interest has a scene with a someone who is not the MC and not another love interest.
Maybe we could get better clarity by using English terms...
cuck: MC is cucked by NPC, whether or not MC is present
bull: MC cucks NPC
rival: MC has to win the affections of an LI from a rival NPC
voyeur: MC watches other people have sex
3p: Player is shown sex scenes between NPCs without MC present, such as when a love interest remembers past adventures
cheater: MC cheats on a partner without their knowledge or consent
cheated: Partner cheats on MC
sharing: MC consensually shares a partner with a non-partner
shared: Partner consensually shares MC with other partner
triangle: Two or more of MCs' partners have sex with each other (there's probably a better term that could be used here)
Did I miss any?
I'm not sure if cuck and bull should be used as broadly as I have them here, since a lot of people think of cucking as specifically having the non-participant in the room watching, so maybe there's a better English term for when a love interest has a scene with a someone who is not the MC and not another love interest.