Is it possible for a woman to rape a man without drugs or alcohol? NSFW?

I’m talking about vaginal intercourse. Not forcing anal or oral. This discussion came up randomly between my boyfriend and I, haha. Well, he claims that it’s not possible for an unattractive girl to rape him because he wouldn’t get an erection since he wouldn’t be turned on by her. If it was a good-looking girl, and if he didn’t want to cheat on me but if she forced him, it might get hard. He is actually very sensitive to losing an erection if he’s distracted or whatever.

My last ex claims that even if the girl was ugly and unattractive, the penis can still get hard because of the stimulation whether you want it or not.

Who is right? I mean, is it still rape if a guy is getting raped by a woman he think is good-looking and gets a hard on although he is forced?