D & R for Mettaton. – Flurry.

D = Dirty Secret (Pretty self explanatory, a dirty secret of theirs)
He prefers to wear dresses, especially in his EX form because it’s juuuuuust hourglass-shaped enough. And heeled boots, of course. 

R = Risk (Are they game to experiment, do they take risks, etc.)
OH IS HE. The EX might as well be for experimentation. Risk, too, is common, but not high risk. Drama and romance, yes, bloodshed, not in the bedroom.