If you plan Dave to join MC later or something like that(since people liked him that much), there should be a option to completely remove the NTR with him, like a small talk with him before it happens, not just hide it. The thing is that a lot of people liked him alot, so if someone you actually like/love has been with other person, you'll automatically hate/feel hurt about it, this is considered ntr because of the feeling, there is a lot ntr games that the ntr happens with caracters that you are not in a relationship but like/cares about.
Also, someone fat, old and bald is hardly not viewed as a ugly bastard
That's all i wanted to say, i hope you make the best decisions in the future, peace.