What does it mean when it says that and how do you get it?

There's literally a link right on that part that explains what it is.

But it went away

If you're on mobile it doesn't show up. Switch to desktop version and you'll see it along with the explanation and everything. If you're too lazy to do that, basically you can click it once every 24 hours and it keeps track of how many people cum on which characters, along with a list of the top 100 characters people cum to