I know this is probably just me, but I love watching people react to seeing a celebrity or like those videos where people play songs to strangers on Omegle. There's just a dopamine rush that goes over my head everytime.

It's also kinda the same thing that occured to me when reading a book, especially when it has reached the climax. But I suspect that for most of the time, it wasn't a dopamine rush, but rather just me walking about and pondering about some other stuff that remotely relates to the book instead of about the book itself.