I'll reiterate what some others have said. This game is definitely not for the anti-NTR crowd. With the exact right dialogue choices (and probably cheats), you can keep your LIs from having sex with other men, but there's a ton of unavoidable stripping and fooling around with other men. It's possible I'm running into some of these things because there's no walkthrough, but that's also an issue.
It's another example of how "non-NTR" routes in NTR games like this and The Roommate are never what non-NTR players actually want.