All ntr is avoidable in the legacy version, at least by the true meaning of the term ("protagonist seeing a loved one being lost to someone else"). At the point where Ann is having sex with her boyfriend, MC is not her lover yet. Kira is just some sort of sex toy anyway, and her scenes also can be avoided mostly.
In the new version, Eric only showed up briefly, no interaction between him and anyone else so far. His influnce will most likely be limited to Ann and Kira, same as in the legacy version.
People should not be so obsessed over the question if a game has other guys in in it or not. If it serves the story, I am cool with almost anything really. Adding or removing something just for the sake of it (because some people want it or want it to be removed) ... THAT's the no-go for me.