There's a split second where Dionysus debates not doing what he's about to do, because of the wood floors and his body that aged into its late 40s, but then he decides he doesn't care about any of that, and whatever knee pain he has later he can just deal with. So, having made up his mind, he starts leaving a trail of kisses down Grantaire's cheek, neck, chest, tummy, and then finally he has to pull previously discussed translucent trousers down out of the way.