@Xxjuggernaut Well yes, but actually no. It use as a trope in fiction. Not cheat in context. So, in his perspective, he get NTR
I mean, it pretty much like two childhoodfriend (not) going out thing
NTR is the act of a significant other being taken away (willingly or unwillingly) or having sexual relations with another person (willingly or unwillingly), usually behind their other SO's back or even in front of them in some circumstances. In this circumstance, it is not NTR, simply because there is not a lover relationship between any of them really(yet), so there is no one to be taken or to be cheated on. Senjo can go with any of them, and the others won't have anything to cry about because she isn't theirs. Until either Takamura or Hoshi confess and Henjo accepts, her going with another person wouldn't be NTR.
@Shootyagoo
Then one side crush can work too. I see a lot of hentai have the tag despite they in no relationship as long as it use to create that same emotion. And we all know hentai is a trustworthy source of information, so...
@Tcof Yes and yes.It still isn't NTR. He's not hers. By default. She has no feelings for him and never has. The dude was friendzoned. Hell, the kid didn't even confess. She doensn't have a clue to any of his feelings.
Well, I've seen hentai tagged as "rape" where no rape is going on (neither explicitly nor implied).
Remember that these tags are made by the same people that don't understand what NTR is.
@Xxjuggernaut and @Shootyagoo are correct. This isn't NTR, simply because Senko and delinquent guy aren't lovers. Being lovers is the prerequisite for NTR. No lovers, no NTR.