I understand what you meant.
Like, you don't want your mom/wife to know that you are a cuckson/cuckhubby, meanwhile enjoying the show through secret camera, PI and other means.
The excitement... like imagine you are a middle school boy sitting together in dinner table with your mom and dad of mid 30s, your parents are supposed to be happily married, it's like normal family dinner... your mom telling your dad how she has lots of fun in her friends house etc etc....but you are finishing the dinner in silence, your mom doesn't know that you caught her fucking the neighbour Mr. Clerk when you return home from school early, the lovers didn't noticed you as they are too busy doing their "thing" and you are silent like a cat.
Now your mom acting like a loving caring wife, if you open your mouth she would get kicked out of house in the very instance but you don't want to do that.... your mom despite having a still handsome well paid corporate husband decided to fuck that dirty old bald bastard makes you hard, you were thinking about it whole day by that point, masterbating on the mental images of her ... you want to know more, did the guy fuck mommy in the ass too?? Or like did he came inside mom? Would she get pregnant? If that happens would your father suspect a single thing? Or is swalloed it in the end?
These kind of emotions used to eaten me up.