A Heian Hikago fic! That sounds quite awesome. And I agree, Kamo no Akira is just priceless.

For nicovideo, there's an option on the bottom right (I think it's on the bottom right) that looks like a speech bubble. If you click on that, it'll make the comments go away! The text running across the top is by other users. They're displayed at the timestamp of where people make their comments. I find them quite fun to read, but I do turn them off whenever I need to make screencaps.