Why are you saying he's getting NTR'd? He isn't in a relationship with his captain. It's more a case of "I loved her first!". =/ Kids these days brand everything NTR.
Headsup: I'm not taking a side here. So no arguements pls 🥹
But it's always been the mangakas themself who write/tag BSS as NTR. It's even written in the covers. I guess it's the emotional impact the MC(losing POV) and readers get, especially when the FL also loved him.
Hence also why they don't just solely use the word cheating.
Here's a tiny amount of my reads though:
(the me who promised not to go above 10K is crying)
i didnt remember this young man even appear in WN but with how the manga somehow keep the story more expanded compared to WN maybe this part also additional portion