Greenmail is, quite logically, blackmail of a different color.

Oh, is this a blackmail, then?

Hold on! Watch and pray! God gives nice answers to slanders! You can trust Him for answers, for He can do wonders!

The bonds of friendship dwindle with age, Oliver. But a little blackmail lasts forever.

It's quite nice to have a bit more color on the lips during wintertime. And it's festive, isn't it?

You can't use blackmail on someone who doesn't know anything about the hold you have on them.