I really love this kind of story, similar to Genre "Uraaka " or "secret account" .
where your crush, or friends or at least someone you know daily, who seems to have normal mundane life, actually doing something naughty behind the scene and you happen to found this "secret life". and then the next days, you found them acting like usual, like nothing has happen at all. so you too, interact with them as usual. but deep down you know, you're gonna fap to her "secret" later that night. its not really an NTR, more like BSS or voyeurisms.
one thing that i kinda dislike about this story is how easily the girl show her real face to the stream. atleast make it showing her face an accident, unintentional, like her masks came off because their activities were too intense. or she lift her mask partially for Blowjob scene, etc.
anyway, if you guys can recommend a story similar to this, i would be delightful.