I'm disagreeing about the part where you said that he might just be turned on by the whole thing. When it involves cheating and feelings of emotional betrayal, it doesn't usually become a turn on, unless the whole thing drives him so mad that it causes his entire pleasure and rewards system to be turned upside down.
...Well, now, this is taking us right into the very heart of "cuckolding". I'd like to share with you (since you may not have read it in my other posts) an experience I had while in college. My sophomore year I met and started dating a freshman female who, by all 3 of my roommates, was one of the most beautiful women I had ever dated ( prior to my wife, of course
), and for about 4 months or so we were almost inseparable. My roommates were so envious, especially on weekends when she would often sleep over and I'd bang her a half dozen times while they listened.
... Anyways, the relationship started to change, where she would have other things "she had to do", and I found out, through one of her so-called friends that she was banging a couple other guys besides me. My GF had said she was going home for a weekend, but instead was entertaining this guy at her place for the weekend. I couldn't believe it and drove to her place to see. It practically destroyed me for over a month, but strangely, when I found out she was fucking other guys, I got an erection and masturbated at least a half dozen times over the visualization of it all. Mind you, I knew nothing of what cuckolding was about back then. The thing is, the overwhelming emotional power ball we get when something like this happens, affects different men in different ways ... some get turned on, while others get turned off. So, some men, when they find out their wives are cheating DO, in fact, strangely find their cheating and the visualization of them fucking other men a Big Turn On.
...She wanted to continue dating me BUT confessed that she wanted to date other guys as well, and I simply could not handle it, so we broke up.
So, therein lies the strange world of cuckolding.